]> git.sesse.net Git - ffmpeg/blobdiff - libavcodec/vp9.c
Merge commit '9b56ac74b170d12027fbc81f581a451a709f1105'
[ffmpeg] / libavcodec / vp9.c
index b9397f58c5449cd55f05aa61e6a64c6def9e2357..c4efd42baf3a6c89ded5f1ed9d65a2d7385cea41 100644 (file)
  * Copyright (C) 2013 Ronald S. Bultje <rsbultje gmail com>
  * Copyright (C) 2013 Clément Bœsch <u pkh me>
  *
- * This file is part of Libav.
+ * This file is part of FFmpeg.
  *
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
- * Libav is distributed in the hope that it will be useful,
+ * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "libavutil/avassert.h"
-
 #include "avcodec.h"
 #include "get_bits.h"
 #include "internal.h"
+#include "thread.h"
 #include "videodsp.h"
 #include "vp56.h"
 #include "vp9.h"
 #include "vp9data.h"
+#include "vp9dsp.h"
+#include "libavutil/avassert.h"
+#include "libavutil/pixdesc.h"
 
 #define VP9_SYNCCODE 0x498342
-#define MAX_PROB 255
 
-static void vp9_decode_flush(AVCodecContext *avctx)
+enum CompPredMode {
+    PRED_SINGLEREF,
+    PRED_COMPREF,
+    PRED_SWITCHABLE,
+};
+
+enum BlockLevel {
+    BL_64X64,
+    BL_32X32,
+    BL_16X16,
+    BL_8X8,
+};
+
+enum BlockSize {
+    BS_64x64,
+    BS_64x32,
+    BS_32x64,
+    BS_32x32,
+    BS_32x16,
+    BS_16x32,
+    BS_16x16,
+    BS_16x8,
+    BS_8x16,
+    BS_8x8,
+    BS_8x4,
+    BS_4x8,
+    BS_4x4,
+    N_BS_SIZES,
+};
+
+struct VP9mvrefPair {
+    VP56mv mv[2];
+    int8_t ref[2];
+};
+
+typedef struct VP9Frame {
+    ThreadFrame tf;
+    AVBufferRef *extradata;
+    uint8_t *segmentation_map;
+    struct VP9mvrefPair *mv;
+    int uses_2pass;
+} VP9Frame;
+
+struct VP9Filter {
+    uint8_t level[8 * 8];
+    uint8_t /* bit=col */ mask[2 /* 0=y, 1=uv */][2 /* 0=col, 1=row */]
+                              [8 /* rows */][4 /* 0=16, 1=8, 2=4, 3=inner4 */];
+};
+
+typedef struct VP9Block {
+    uint8_t seg_id, intra, comp, ref[2], mode[4], uvmode, skip;
+    enum FilterMode filter;
+    VP56mv mv[4 /* b_idx */][2 /* ref */];
+    enum BlockSize bs;
+    enum TxfmMode tx, uvtx;
+    enum BlockLevel bl;
+    enum BlockPartition bp;
+} VP9Block;
+
+typedef struct VP9Context {
+    VP9DSPContext dsp;
+    VideoDSPContext vdsp;
+    GetBitContext gb;
+    VP56RangeCoder c;
+    VP56RangeCoder *c_b;
+    unsigned c_b_size;
+    VP9Block *b_base, *b;
+    int pass;
+    int row, row7, col, col7;
+    uint8_t *dst[3];
+    ptrdiff_t y_stride, uv_stride;
+
+    // bitstream header
+    uint8_t keyframe, last_keyframe;
+    uint8_t last_bpp, bpp, bpp_index, bytesperpixel;
+    uint8_t invisible;
+    uint8_t use_last_frame_mvs;
+    uint8_t errorres;
+    uint8_t ss_h, ss_v;
+    uint8_t intraonly;
+    uint8_t resetctx;
+    uint8_t refreshrefmask;
+    uint8_t highprecisionmvs;
+    enum FilterMode filtermode;
+    uint8_t allowcompinter;
+    uint8_t fixcompref;
+    uint8_t refreshctx;
+    uint8_t parallelmode;
+    uint8_t framectxid;
+    uint8_t refidx[3];
+    uint8_t signbias[3];
+    uint8_t varcompref[2];
+    ThreadFrame refs[8], next_refs[8];
+#define CUR_FRAME 0
+#define REF_FRAME_MVPAIR 1
+#define REF_FRAME_SEGMAP 2
+    VP9Frame frames[3];
+
+    struct {
+        uint8_t level;
+        int8_t sharpness;
+        uint8_t lim_lut[64];
+        uint8_t mblim_lut[64];
+    } filter;
+    struct {
+        uint8_t enabled;
+        int8_t mode[2];
+        int8_t ref[4];
+    } lf_delta;
+    uint8_t yac_qi;
+    int8_t ydc_qdelta, uvdc_qdelta, uvac_qdelta;
+    uint8_t lossless;
+#define MAX_SEGMENT 8
+    struct {
+        uint8_t enabled;
+        uint8_t temporal;
+        uint8_t absolute_vals;
+        uint8_t update_map;
+        uint8_t ignore_refmap;
+        struct {
+            uint8_t q_enabled;
+            uint8_t lf_enabled;
+            uint8_t ref_enabled;
+            uint8_t skip_enabled;
+            uint8_t ref_val;
+            int16_t q_val;
+            int8_t lf_val;
+            int16_t qmul[2][2];
+            uint8_t lflvl[4][2];
+        } feat[MAX_SEGMENT];
+    } segmentation;
+    struct {
+        unsigned log2_tile_cols, log2_tile_rows;
+        unsigned tile_cols, tile_rows;
+        unsigned tile_row_start, tile_row_end, tile_col_start, tile_col_end;
+    } tiling;
+    unsigned sb_cols, sb_rows, rows, cols;
+    struct {
+        prob_context p;
+        uint8_t coef[4][2][2][6][6][3];
+    } prob_ctx[4];
+    struct {
+        prob_context p;
+        uint8_t coef[4][2][2][6][6][11];
+        uint8_t seg[7];
+        uint8_t segpred[3];
+    } prob;
+    struct {
+        unsigned y_mode[4][10];
+        unsigned uv_mode[10][10];
+        unsigned filter[4][3];
+        unsigned mv_mode[7][4];
+        unsigned intra[4][2];
+        unsigned comp[5][2];
+        unsigned single_ref[5][2][2];
+        unsigned comp_ref[5][2];
+        unsigned tx32p[2][4];
+        unsigned tx16p[2][3];
+        unsigned tx8p[2][2];
+        unsigned skip[3][2];
+        unsigned mv_joint[4];
+        struct {
+            unsigned sign[2];
+            unsigned classes[11];
+            unsigned class0[2];
+            unsigned bits[10][2];
+            unsigned class0_fp[2][4];
+            unsigned fp[4];
+            unsigned class0_hp[2];
+            unsigned hp[2];
+        } mv_comp[2];
+        unsigned partition[4][4][4];
+        unsigned coef[4][2][2][6][6][3];
+        unsigned eob[4][2][2][6][6][2];
+    } counts;
+    enum TxfmMode txfmmode;
+    enum CompPredMode comppredmode;
+
+    // contextual (left/above) cache
+    DECLARE_ALIGNED(16, uint8_t, left_y_nnz_ctx)[16];
+    DECLARE_ALIGNED(16, uint8_t, left_mode_ctx)[16];
+    DECLARE_ALIGNED(16, VP56mv, left_mv_ctx)[16][2];
+    DECLARE_ALIGNED(16, uint8_t, left_uv_nnz_ctx)[2][16];
+    DECLARE_ALIGNED(8, uint8_t, left_partition_ctx)[8];
+    DECLARE_ALIGNED(8, uint8_t, left_skip_ctx)[8];
+    DECLARE_ALIGNED(8, uint8_t, left_txfm_ctx)[8];
+    DECLARE_ALIGNED(8, uint8_t, left_segpred_ctx)[8];
+    DECLARE_ALIGNED(8, uint8_t, left_intra_ctx)[8];
+    DECLARE_ALIGNED(8, uint8_t, left_comp_ctx)[8];
+    DECLARE_ALIGNED(8, uint8_t, left_ref_ctx)[8];
+    DECLARE_ALIGNED(8, uint8_t, left_filter_ctx)[8];
+    uint8_t *above_partition_ctx;
+    uint8_t *above_mode_ctx;
+    // FIXME maybe merge some of the below in a flags field?
+    uint8_t *above_y_nnz_ctx;
+    uint8_t *above_uv_nnz_ctx[2];
+    uint8_t *above_skip_ctx; // 1bit
+    uint8_t *above_txfm_ctx; // 2bit
+    uint8_t *above_segpred_ctx; // 1bit
+    uint8_t *above_intra_ctx; // 1bit
+    uint8_t *above_comp_ctx; // 1bit
+    uint8_t *above_ref_ctx; // 2bit
+    uint8_t *above_filter_ctx;
+    VP56mv (*above_mv_ctx)[2];
+
+    // whole-frame cache
+    uint8_t *intra_pred_data[3];
+    struct VP9Filter *lflvl;
+    DECLARE_ALIGNED(32, uint8_t, edge_emu_buffer)[135 * 144 * 2];
+
+    // block reconstruction intermediates
+    int block_alloc_using_2pass;
+    int16_t *block_base, *block, *uvblock_base[2], *uvblock[2];
+    uint8_t *eob_base, *uveob_base[2], *eob, *uveob[2];
+    struct { int x, y; } min_mv, max_mv;
+    DECLARE_ALIGNED(32, uint8_t, tmp_y)[64 * 64 * 2];
+    DECLARE_ALIGNED(32, uint8_t, tmp_uv)[2][64 * 64 * 2];
+    uint16_t mvscale[3][2];
+    uint8_t mvstep[3][2];
+} VP9Context;
+
+static const uint8_t bwh_tab[2][N_BS_SIZES][2] = {
+    {
+        { 16, 16 }, { 16, 8 }, { 8, 16 }, { 8, 8 }, { 8, 4 }, { 4, 8 },
+        { 4, 4 }, { 4, 2 }, { 2, 4 }, { 2, 2 }, { 2, 1 }, { 1, 2 }, { 1, 1 },
+    }, {
+        { 8, 8 }, { 8, 4 }, { 4, 8 }, { 4, 4 }, { 4, 2 }, { 2, 4 },
+        { 2, 2 }, { 2, 1 }, { 1, 2 }, { 1, 1 }, { 1, 1 }, { 1, 1 }, { 1, 1 },
+    }
+};
+
+static int vp9_alloc_frame(AVCodecContext *ctx, VP9Frame *f)
 {
-    VP9Context *s = avctx->priv_data;
-    int i;
+    VP9Context *s = ctx->priv_data;
+    int ret, sz;
+
+    if ((ret = ff_thread_get_buffer(ctx, &f->tf, AV_GET_BUFFER_FLAG_REF)) < 0)
+        return ret;
+    sz = 64 * s->sb_cols * s->sb_rows;
+    if (!(f->extradata = av_buffer_allocz(sz * (1 + sizeof(struct VP9mvrefPair))))) {
+        ff_thread_release_buffer(ctx, &f->tf);
+        return AVERROR(ENOMEM);
+    }
+
+    f->segmentation_map = f->extradata->data;
+    f->mv = (struct VP9mvrefPair *) (f->extradata->data + sz);
+
+    return 0;
+}
+
+static void vp9_unref_frame(AVCodecContext *ctx, VP9Frame *f)
+{
+    ff_thread_release_buffer(ctx, &f->tf);
+    av_buffer_unref(&f->extradata);
+}
+
+static int vp9_ref_frame(AVCodecContext *ctx, VP9Frame *dst, VP9Frame *src)
+{
+    int res;
+
+    if ((res = ff_thread_ref_frame(&dst->tf, &src->tf)) < 0) {
+        return res;
+    } else if (!(dst->extradata = av_buffer_ref(src->extradata))) {
+        vp9_unref_frame(ctx, dst);
+        return AVERROR(ENOMEM);
+    }
 
-    for (i = 0; i < FF_ARRAY_ELEMS(s->refs); i++)
-        av_frame_unref(s->refs[i]);
+    dst->segmentation_map = src->segmentation_map;
+    dst->mv = src->mv;
+    dst->uses_2pass = src->uses_2pass;
+
+    return 0;
 }
 
-static int update_size(AVCodecContext *avctx, int w, int h)
+static int update_size(AVCodecContext *ctx, int w, int h, enum AVPixelFormat fmt)
 {
-    VP9Context *s = avctx->priv_data;
+    VP9Context *s = ctx->priv_data;
     uint8_t *p;
+    int bytesperpixel = s->bytesperpixel;
 
-    if (s->above_partition_ctx && w == avctx->width && h == avctx->height)
-        return 0;
+    av_assert0(w > 0 && h > 0);
 
-    vp9_decode_flush(avctx);
+    if (s->intra_pred_data[0] && w == ctx->width && h == ctx->height && ctx->pix_fmt == fmt)
+        return 0;
 
-    if (w <= 0 || h <= 0)
-        return AVERROR_INVALIDDATA;
+    ctx->width   = w;
+    ctx->height  = h;
+    ctx->pix_fmt = fmt;
+    s->sb_cols   = (w + 63) >> 6;
+    s->sb_rows   = (h + 63) >> 6;
+    s->cols      = (w + 7) >> 3;
+    s->rows      = (h + 7) >> 3;
 
-    avctx->width  = w;
-    avctx->height = h;
-    s->sb_cols    = (w + 63) >> 6;
-    s->sb_rows    = (h + 63) >> 6;
-    s->cols       = (w +  7) >> 3;
-    s->rows       = (h +  7) >> 3;
-
-#define assign(var, type, n) var = (type)p; p += s->sb_cols * n * sizeof(*var)
-    av_free(s->above_partition_ctx);
-    p = av_malloc(s->sb_cols *
-                  (240 + sizeof(*s->lflvl) + 16 * sizeof(*s->above_mv_ctx) +
-                   64 * s->sb_rows * (1 + sizeof(*s->mv[0]) * 2)));
+#define assign(var, type, n) var = (type) p; p += s->sb_cols * (n) * sizeof(*var)
+    av_freep(&s->intra_pred_data[0]);
+    // FIXME we slightly over-allocate here for subsampled chroma, but a little
+    // bit of padding shouldn't affect performance...
+    p = av_malloc(s->sb_cols * (128 + 192 * bytesperpixel +
+                                sizeof(*s->lflvl) + 16 * sizeof(*s->above_mv_ctx)));
     if (!p)
         return AVERROR(ENOMEM);
-    assign(s->above_partition_ctx, uint8_t *,     8);
-    assign(s->above_skip_ctx,      uint8_t *,     8);
-    assign(s->above_txfm_ctx,      uint8_t *,     8);
-    assign(s->above_mode_ctx,      uint8_t *,    16);
-    assign(s->above_y_nnz_ctx,     uint8_t *,    16);
-    assign(s->above_uv_nnz_ctx[0], uint8_t *,     8);
-    assign(s->above_uv_nnz_ctx[1], uint8_t *,     8);
-    assign(s->intra_pred_data[0],  uint8_t *,    64);
-    assign(s->intra_pred_data[1],  uint8_t *,    32);
-    assign(s->intra_pred_data[2],  uint8_t *,    32);
-    assign(s->above_segpred_ctx,   uint8_t *,     8);
-    assign(s->above_intra_ctx,     uint8_t *,     8);
-    assign(s->above_comp_ctx,      uint8_t *,     8);
-    assign(s->above_ref_ctx,       uint8_t *,     8);
-    assign(s->above_filter_ctx,    uint8_t *,     8);
-    assign(s->lflvl,               VP9Filter *,   1);
-    assign(s->above_mv_ctx,        VP56mv(*)[2], 16);
-    assign(s->segmentation_map,    uint8_t *,      64 * s->sb_rows);
-    assign(s->mv[0],               VP9MVRefPair *, 64 * s->sb_rows);
-    assign(s->mv[1],               VP9MVRefPair *, 64 * s->sb_rows);
+    assign(s->intra_pred_data[0],  uint8_t *,             64 * bytesperpixel);
+    assign(s->intra_pred_data[1],  uint8_t *,             64 * bytesperpixel);
+    assign(s->intra_pred_data[2],  uint8_t *,             64 * bytesperpixel);
+    assign(s->above_y_nnz_ctx,     uint8_t *,             16);
+    assign(s->above_mode_ctx,      uint8_t *,             16);
+    assign(s->above_mv_ctx,        VP56mv(*)[2],          16);
+    assign(s->above_uv_nnz_ctx[0], uint8_t *,             16);
+    assign(s->above_uv_nnz_ctx[1], uint8_t *,             16);
+    assign(s->above_partition_ctx, uint8_t *,              8);
+    assign(s->above_skip_ctx,      uint8_t *,              8);
+    assign(s->above_txfm_ctx,      uint8_t *,              8);
+    assign(s->above_segpred_ctx,   uint8_t *,              8);
+    assign(s->above_intra_ctx,     uint8_t *,              8);
+    assign(s->above_comp_ctx,      uint8_t *,              8);
+    assign(s->above_ref_ctx,       uint8_t *,              8);
+    assign(s->above_filter_ctx,    uint8_t *,              8);
+    assign(s->lflvl,               struct VP9Filter *,     1);
 #undef assign
 
+    // these will be re-allocated a little later
+    av_freep(&s->b_base);
+    av_freep(&s->block_base);
+
+    if (s->bpp != s->last_bpp) {
+        ff_vp9dsp_init(&s->dsp, s->bpp);
+        ff_videodsp_init(&s->vdsp, s->bpp);
+        s->last_bpp = s->bpp;
+    }
+
+    return 0;
+}
+
+static int update_block_buffers(AVCodecContext *ctx)
+{
+    VP9Context *s = ctx->priv_data;
+    int chroma_blocks, chroma_eobs, bytesperpixel = s->bytesperpixel;
+
+    if (s->b_base && s->block_base && s->block_alloc_using_2pass == s->frames[CUR_FRAME].uses_2pass)
+        return 0;
+
+    av_free(s->b_base);
+    av_free(s->block_base);
+    chroma_blocks = 64 * 64 >> (s->ss_h + s->ss_v);
+    chroma_eobs   = 16 * 16 >> (s->ss_h + s->ss_v);
+    if (s->frames[CUR_FRAME].uses_2pass) {
+        int sbs = s->sb_cols * s->sb_rows;
+
+        s->b_base = av_malloc_array(s->cols * s->rows, sizeof(VP9Block));
+        s->block_base = av_mallocz(((64 * 64 + 2 * chroma_blocks) * bytesperpixel * sizeof(int16_t) +
+                                    16 * 16 + 2 * chroma_eobs) * sbs);
+        if (!s->b_base || !s->block_base)
+            return AVERROR(ENOMEM);
+        s->uvblock_base[0] = s->block_base + sbs * 64 * 64 * bytesperpixel;
+        s->uvblock_base[1] = s->uvblock_base[0] + sbs * chroma_blocks * bytesperpixel;
+        s->eob_base = (uint8_t *) (s->uvblock_base[1] + sbs * chroma_blocks * bytesperpixel);
+        s->uveob_base[0] = s->eob_base + 16 * 16 * sbs;
+        s->uveob_base[1] = s->uveob_base[0] + chroma_eobs * sbs;
+    } else {
+        s->b_base = av_malloc(sizeof(VP9Block));
+        s->block_base = av_mallocz((64 * 64 + 2 * chroma_blocks) * bytesperpixel * sizeof(int16_t) +
+                                   16 * 16 + 2 * chroma_eobs);
+        if (!s->b_base || !s->block_base)
+            return AVERROR(ENOMEM);
+        s->uvblock_base[0] = s->block_base + 64 * 64 * bytesperpixel;
+        s->uvblock_base[1] = s->uvblock_base[0] + chroma_blocks * bytesperpixel;
+        s->eob_base = (uint8_t *) (s->uvblock_base[1] + chroma_blocks * bytesperpixel);
+        s->uveob_base[0] = s->eob_base + 16 * 16;
+        s->uveob_base[1] = s->uveob_base[0] + chroma_eobs;
+    }
+    s->block_alloc_using_2pass = s->frames[CUR_FRAME].uses_2pass;
+
     return 0;
 }
 
-// The sign bit is at the end, not the start, of a bit sequence
-static av_always_inline int get_bits_with_sign(GetBitContext *gb, int n)
+// for some reason the sign bit is at the end, not the start, of a bit sequence
+static av_always_inline int get_sbits_inv(GetBitContext *gb, int n)
 {
     int v = get_bits(gb, n);
     return get_bits1(gb) ? -v : v;
@@ -104,17 +419,13 @@ static av_always_inline int get_bits_with_sign(GetBitContext *gb, int n)
 
 static av_always_inline int inv_recenter_nonneg(int v, int m)
 {
-    if (v > 2 * m)
-        return v;
-    if (v & 1)
-        return m - ((v + 1) >> 1);
-    return m + (v >> 1);
+    return v > 2 * m ? v : v & 1 ? m - ((v + 1) >> 1) : m + (v >> 1);
 }
 
 // differential forward probability updates
 static int update_prob(VP56RangeCoder *c, int p)
 {
-    static const int inv_map_table[MAX_PROB - 1] = {
+    static const int inv_map_table[254] = {
           7,  20,  33,  46,  59,  72,  85,  98, 111, 124, 137, 150, 163, 176,
         189, 202, 215, 228, 241, 254,   1,   2,   3,   4,   5,   6,   8,   9,
          10,  11,  12,  13,  14,  15,  16,  17,  18,  19,  21,  22,  23,  24,
@@ -139,13 +450,13 @@ static int update_prob(VP56RangeCoder *c, int p)
 
     /* This code is trying to do a differential probability update. For a
      * current probability A in the range [1, 255], the difference to a new
-     * probability of any value can be expressed differentially as 1-A, 255-A
+     * probability of any value can be expressed differentially as 1-A,255-A
      * where some part of this (absolute range) exists both in positive as
      * well as the negative part, whereas another part only exists in one
      * half. We're trying to code this shared part differentially, i.e.
      * times two where the value of the lowest bit specifies the sign, and
      * the single part is then coded on top of this. This absolute difference
-     * then again has a value of [0, 254], but a bigger value in this range
+     * then again has a value of [0,254], but a bigger value in this range
      * indicates that we're further away from the original value A, so we
      * can code this as a VLC code, since higher values are increasingly
      * unlikely. The first 20 values in inv_map_table[] allow 'cheap, rough'
@@ -160,101 +471,141 @@ static int update_prob(VP56RangeCoder *c, int p)
         d = vp8_rac_get_uint(c, 5) + 32;
     } else {
         d = vp8_rac_get_uint(c, 7);
-        if (d >= 65) {
+        if (d >= 65)
             d = (d << 1) - 65 + vp8_rac_get(c);
-            d = av_clip(d, 0, MAX_PROB - 65 - 1);
-        }
         d += 64;
     }
 
-    return p <= 128
-           ?   1 + inv_recenter_nonneg(inv_map_table[d], p - 1)
-           : 255 - inv_recenter_nonneg(inv_map_table[d], 255 - p);
+    return p <= 128 ? 1 + inv_recenter_nonneg(inv_map_table[d], p - 1) :
+                    255 - inv_recenter_nonneg(inv_map_table[d], 255 - p);
 }
 
-static int decode_frame_header(AVCodecContext *avctx,
+static enum AVPixelFormat read_colorspace_details(AVCodecContext *ctx)
+{
+    static const enum AVColorSpace colorspaces[8] = {
+        AVCOL_SPC_UNSPECIFIED, AVCOL_SPC_BT470BG, AVCOL_SPC_BT709, AVCOL_SPC_SMPTE170M,
+        AVCOL_SPC_SMPTE240M, AVCOL_SPC_BT2020_NCL, AVCOL_SPC_RESERVED, AVCOL_SPC_RGB,
+    };
+    VP9Context *s = ctx->priv_data;
+    enum AVPixelFormat res;
+    int bits = ctx->profile <= 1 ? 0 : 1 + get_bits1(&s->gb); // 0:8, 1:10, 2:12
+
+    s->bpp_index = bits;
+    s->bpp = 8 + bits * 2;
+    s->bytesperpixel = (7 + s->bpp) >> 3;
+    ctx->colorspace = colorspaces[get_bits(&s->gb, 3)];
+    if (ctx->colorspace == AVCOL_SPC_RGB) { // RGB = profile 1
+        static const enum AVPixelFormat pix_fmt_rgb[3] = {
+            AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRP10, AV_PIX_FMT_GBRP12
+        };
+        if (ctx->profile & 1) {
+            s->ss_h = s->ss_v = 1;
+            res = pix_fmt_rgb[bits];
+            ctx->color_range = AVCOL_RANGE_JPEG;
+        } else {
+            av_log(ctx, AV_LOG_ERROR, "RGB not supported in profile %d\n",
+                   ctx->profile);
+            return AVERROR_INVALIDDATA;
+        }
+    } else {
+        static const enum AVPixelFormat pix_fmt_for_ss[3][2 /* v */][2 /* h */] = {
+            { { AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P },
+              { AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV420P } },
+            { { AV_PIX_FMT_YUV444P10, AV_PIX_FMT_YUV422P10 },
+              { AV_PIX_FMT_YUV440P10, AV_PIX_FMT_YUV420P10 } },
+            { { AV_PIX_FMT_YUV444P12, AV_PIX_FMT_YUV422P12 },
+              { AV_PIX_FMT_YUV440P12, AV_PIX_FMT_YUV420P12 } }
+        };
+        ctx->color_range = get_bits1(&s->gb) ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;
+        if (ctx->profile & 1) {
+            s->ss_h = get_bits1(&s->gb);
+            s->ss_v = get_bits1(&s->gb);
+            if ((res = pix_fmt_for_ss[bits][s->ss_v][s->ss_h]) == AV_PIX_FMT_YUV420P) {
+                av_log(ctx, AV_LOG_ERROR, "YUV 4:2:0 not supported in profile %d\n",
+                       ctx->profile);
+                return AVERROR_INVALIDDATA;
+            } else if (get_bits1(&s->gb)) {
+                av_log(ctx, AV_LOG_ERROR, "Profile %d color details reserved bit set\n",
+                       ctx->profile);
+                return AVERROR_INVALIDDATA;
+            }
+        } else {
+            s->ss_h = s->ss_v = 1;
+            res = pix_fmt_for_ss[bits][1][1];
+        }
+    }
+
+    return res;
+}
+
+static int decode_frame_header(AVCodecContext *ctx,
                                const uint8_t *data, int size, int *ref)
 {
-    VP9Context *s = avctx->priv_data;
-    int c, i, j, k, l, m, n, w, h, max, size2, ret, sharp;
+    VP9Context *s = ctx->priv_data;
+    int c, i, j, k, l, m, n, w, h, max, size2, res, sharp;
+    enum AVPixelFormat fmt = ctx->pix_fmt;
     int last_invisible;
     const uint8_t *data2;
 
     /* general header */
-    if ((ret = init_get_bits8(&s->gb, data, size)) < 0) {
-        av_log(avctx, AV_LOG_ERROR, "Failed to initialize bitstream reader\n");
-        return ret;
+    if ((res = init_get_bits8(&s->gb, data, size)) < 0) {
+        av_log(ctx, AV_LOG_ERROR, "Failed to initialize bitstream reader\n");
+        return res;
     }
     if (get_bits(&s->gb, 2) != 0x2) { // frame marker
-        av_log(avctx, AV_LOG_ERROR, "Invalid frame marker\n");
+        av_log(ctx, AV_LOG_ERROR, "Invalid frame marker\n");
         return AVERROR_INVALIDDATA;
     }
-    s->profile = get_bits1(&s->gb);
-    if (get_bits1(&s->gb)) { // reserved bit
-        av_log(avctx, AV_LOG_ERROR, "Reserved bit should be zero\n");
+    ctx->profile  = get_bits1(&s->gb);
+    ctx->profile |= get_bits1(&s->gb) << 1;
+    if (ctx->profile == 3) ctx->profile += get_bits1(&s->gb);
+    if (ctx->profile > 3) {
+        av_log(ctx, AV_LOG_ERROR, "Profile %d is not yet supported\n", ctx->profile);
         return AVERROR_INVALIDDATA;
     }
     if (get_bits1(&s->gb)) {
         *ref = get_bits(&s->gb, 3);
         return 0;
     }
-
-    s->last_keyframe = s->keyframe;
-    s->keyframe      = !get_bits1(&s->gb);
-
-    last_invisible = s->invisible;
-    s->invisible   = !get_bits1(&s->gb);
-    s->errorres    = get_bits1(&s->gb);
-    // FIXME disable this upon resolution change
+    s->last_keyframe  = s->keyframe;
+    s->keyframe       = !get_bits1(&s->gb);
+    last_invisible    = s->invisible;
+    s->invisible      = !get_bits1(&s->gb);
+    s->errorres       = get_bits1(&s->gb);
     s->use_last_frame_mvs = !s->errorres && !last_invisible;
-
     if (s->keyframe) {
         if (get_bits_long(&s->gb, 24) != VP9_SYNCCODE) { // synccode
-            av_log(avctx, AV_LOG_ERROR, "Invalid sync code\n");
-            return AVERROR_INVALIDDATA;
-        }
-        s->colorspace = get_bits(&s->gb, 3);
-        if (s->colorspace == 7) { // RGB = profile 1
-            av_log(avctx, AV_LOG_ERROR, "RGB not supported in profile 0\n");
+            av_log(ctx, AV_LOG_ERROR, "Invalid sync code\n");
             return AVERROR_INVALIDDATA;
         }
-        s->fullrange = get_bits1(&s->gb);
-
-        // subsampling bits
-        if (s->profile == 1 || s->profile == 3) {
-            s->sub_x = get_bits1(&s->gb);
-            s->sub_y = get_bits1(&s->gb);
-            if (s->sub_x && s->sub_y) {
-                av_log(avctx, AV_LOG_ERROR,
-                       "4:2:0 color not supported in profile 1 or 3\n");
-                return AVERROR_INVALIDDATA;
-            }
-            if (get_bits1(&s->gb)) { // reserved bit
-                av_log(avctx, AV_LOG_ERROR, "Reserved bit should be zero\n");
-                return AVERROR_INVALIDDATA;
-            }
-        } else {
-            s->sub_x = s->sub_y = 1;
-        }
-        if (!s->sub_x || !s->sub_y) {
-            avpriv_report_missing_feature(avctx, "Subsampling %d:%d",
-                                          s->sub_x, s->sub_y);
-            return AVERROR_PATCHWELCOME;
-        }
-
+        if ((fmt = read_colorspace_details(ctx)) < 0)
+            return fmt;
+        // for profile 1, here follows the subsampling bits
         s->refreshrefmask = 0xff;
         w = get_bits(&s->gb, 16) + 1;
         h = get_bits(&s->gb, 16) + 1;
         if (get_bits1(&s->gb)) // display size
             skip_bits(&s->gb, 32);
     } else {
-        s->intraonly = s->invisible ? get_bits1(&s->gb) : 0;
-        s->resetctx  = s->errorres ? 0 : get_bits(&s->gb, 2);
+        s->intraonly  = s->invisible ? get_bits1(&s->gb) : 0;
+        s->resetctx   = s->errorres ? 0 : get_bits(&s->gb, 2);
         if (s->intraonly) {
             if (get_bits_long(&s->gb, 24) != VP9_SYNCCODE) { // synccode
-                av_log(avctx, AV_LOG_ERROR, "Invalid sync code\n");
+                av_log(ctx, AV_LOG_ERROR, "Invalid sync code\n");
                 return AVERROR_INVALIDDATA;
             }
+            if (ctx->profile == 1) {
+                if ((fmt = read_colorspace_details(ctx)) < 0)
+                    return fmt;
+            } else {
+                s->ss_h = s->ss_v = 1;
+                s->bpp = 8;
+                s->bpp_index = 0;
+                s->bytesperpixel = 1;
+                fmt = AV_PIX_FMT_YUV420P;
+                ctx->colorspace = AVCOL_SPC_BT470BG;
+                ctx->color_range = AVCOL_RANGE_JPEG;
+            }
             s->refreshrefmask = get_bits(&s->gb, 8);
             w = get_bits(&s->gb, 16) + 1;
             h = get_bits(&s->gb, 16) + 1;
@@ -263,38 +614,42 @@ static int decode_frame_header(AVCodecContext *avctx,
         } else {
             s->refreshrefmask = get_bits(&s->gb, 8);
             s->refidx[0]      = get_bits(&s->gb, 3);
-            s->signbias[0]    = get_bits1(&s->gb);
+            s->signbias[0]    = get_bits1(&s->gb) && !s->errorres;
             s->refidx[1]      = get_bits(&s->gb, 3);
-            s->signbias[1]    = get_bits1(&s->gb);
+            s->signbias[1]    = get_bits1(&s->gb) && !s->errorres;
             s->refidx[2]      = get_bits(&s->gb, 3);
-            s->signbias[2]    = get_bits1(&s->gb);
-            if (!s->refs[s->refidx[0]]->buf[0] ||
-                !s->refs[s->refidx[1]]->buf[0] ||
-                !s->refs[s->refidx[2]]->buf[0]) {
-                av_log(avctx, AV_LOG_ERROR,
-                       "Not all references are available\n");
+            s->signbias[2]    = get_bits1(&s->gb) && !s->errorres;
+            if (!s->refs[s->refidx[0]].f->data[0] ||
+                !s->refs[s->refidx[1]].f->data[0] ||
+                !s->refs[s->refidx[2]].f->data[0]) {
+                av_log(ctx, AV_LOG_ERROR, "Not all references are available\n");
                 return AVERROR_INVALIDDATA;
             }
             if (get_bits1(&s->gb)) {
-                w = s->refs[s->refidx[0]]->width;
-                h = s->refs[s->refidx[0]]->height;
+                w = s->refs[s->refidx[0]].f->width;
+                h = s->refs[s->refidx[0]].f->height;
             } else if (get_bits1(&s->gb)) {
-                w = s->refs[s->refidx[1]]->width;
-                h = s->refs[s->refidx[1]]->height;
+                w = s->refs[s->refidx[1]].f->width;
+                h = s->refs[s->refidx[1]].f->height;
             } else if (get_bits1(&s->gb)) {
-                w = s->refs[s->refidx[2]]->width;
-                h = s->refs[s->refidx[2]]->height;
+                w = s->refs[s->refidx[2]].f->width;
+                h = s->refs[s->refidx[2]].f->height;
             } else {
                 w = get_bits(&s->gb, 16) + 1;
                 h = get_bits(&s->gb, 16) + 1;
             }
+            // Note that in this code, "CUR_FRAME" is actually before we
+            // have formally allocated a frame, and thus actually represents
+            // the _last_ frame
+            s->use_last_frame_mvs &= s->frames[CUR_FRAME].tf.f->width == w &&
+                                     s->frames[CUR_FRAME].tf.f->height == h;
             if (get_bits1(&s->gb)) // display size
                 skip_bits(&s->gb, 32);
             s->highprecisionmvs = get_bits1(&s->gb);
-            s->filtermode       = get_bits1(&s->gb) ? FILTER_SWITCHABLE :
-                                  get_bits(&s->gb, 2);
-            s->allowcompinter   = s->signbias[0] != s->signbias[1] ||
-                                  s->signbias[0] != s->signbias[2];
+            s->filtermode = get_bits1(&s->gb) ? FILTER_SWITCHABLE :
+                                                get_bits(&s->gb, 2);
+            s->allowcompinter = (s->signbias[0] != s->signbias[1] ||
+                                 s->signbias[0] != s->signbias[2]);
             if (s->allowcompinter) {
                 if (s->signbias[0] == s->signbias[1]) {
                     s->fixcompref    = 2;
@@ -310,18 +665,52 @@ static int decode_frame_header(AVCodecContext *avctx,
                     s->varcompref[1] = 2;
                 }
             }
+
+            for (i = 0; i < 3; i++) {
+                AVFrame *ref = s->refs[s->refidx[i]].f;
+                int refw = ref->width, refh = ref->height;
+
+                if (ref->format != fmt) {
+                    av_log(ctx, AV_LOG_ERROR,
+                           "Ref pixfmt (%s) did not match current frame (%s)",
+                           av_get_pix_fmt_name(ref->format),
+                           av_get_pix_fmt_name(fmt));
+                    return AVERROR_INVALIDDATA;
+                } else if (refw == w && refh == h) {
+                    s->mvscale[i][0] = s->mvscale[i][1] = 0;
+                } else {
+                    if (w * 2 < refw || h * 2 < refh || w > 16 * refw || h > 16 * refh) {
+                        av_log(ctx, AV_LOG_ERROR,
+                               "Invalid ref frame dimensions %dx%d for frame size %dx%d\n",
+                               refw, refh, w, h);
+                        return AVERROR_INVALIDDATA;
+                    }
+                    s->mvscale[i][0] = (refw << 14) / w;
+                    s->mvscale[i][1] = (refh << 14) / h;
+                    s->mvstep[i][0] = 16 * s->mvscale[i][0] >> 14;
+                    s->mvstep[i][1] = 16 * s->mvscale[i][1] >> 14;
+                }
+            }
         }
     }
-
     s->refreshctx   = s->errorres ? 0 : get_bits1(&s->gb);
     s->parallelmode = s->errorres ? 1 : get_bits1(&s->gb);
     s->framectxid   = c = get_bits(&s->gb, 2);
 
     /* loopfilter header data */
+    if (s->keyframe || s->errorres || s->intraonly) {
+        // reset loopfilter defaults
+        s->lf_delta.ref[0] = 1;
+        s->lf_delta.ref[1] = 0;
+        s->lf_delta.ref[2] = -1;
+        s->lf_delta.ref[3] = -1;
+        s->lf_delta.mode[0] = 0;
+        s->lf_delta.mode[1] = 0;
+    }
     s->filter.level = get_bits(&s->gb, 6);
-    sharp           = get_bits(&s->gb, 3);
-    /* If sharpness changed, reinit lim/mblim LUTs. if it didn't change,
-     * keep the old cache values since they are still valid. */
+    sharp = get_bits(&s->gb, 3);
+    // if sharpness changed, reinit lim/mblim LUTs. if it didn't change, keep
+    // the old cache values since they are still valid
     if (s->filter.sharpness != sharp)
         memset(s->filter.lim_lut, 0, sizeof(s->filter.lim_lut));
     s->filter.sharpness = sharp;
@@ -329,42 +718,51 @@ static int decode_frame_header(AVCodecContext *avctx,
         if (get_bits1(&s->gb)) {
             for (i = 0; i < 4; i++)
                 if (get_bits1(&s->gb))
-                    s->lf_delta.ref[i] = get_bits_with_sign(&s->gb, 6);
+                    s->lf_delta.ref[i] = get_sbits_inv(&s->gb, 6);
             for (i = 0; i < 2; i++)
                 if (get_bits1(&s->gb))
-                    s->lf_delta.mode[i] = get_bits_with_sign(&s->gb, 6);
+                    s->lf_delta.mode[i] = get_sbits_inv(&s->gb, 6);
         }
-    } else {
-        memset(&s->lf_delta, 0, sizeof(s->lf_delta));
     }
 
     /* quantization header data */
     s->yac_qi      = get_bits(&s->gb, 8);
-    s->ydc_qdelta  = get_bits1(&s->gb) ? get_bits_with_sign(&s->gb, 4) : 0;
-    s->uvdc_qdelta = get_bits1(&s->gb) ? get_bits_with_sign(&s->gb, 4) : 0;
-    s->uvac_qdelta = get_bits1(&s->gb) ? get_bits_with_sign(&s->gb, 4) : 0;
+    s->ydc_qdelta  = get_bits1(&s->gb) ? get_sbits_inv(&s->gb, 4) : 0;
+    s->uvdc_qdelta = get_bits1(&s->gb) ? get_sbits_inv(&s->gb, 4) : 0;
+    s->uvac_qdelta = get_bits1(&s->gb) ? get_sbits_inv(&s->gb, 4) : 0;
     s->lossless    = s->yac_qi == 0 && s->ydc_qdelta == 0 &&
                      s->uvdc_qdelta == 0 && s->uvac_qdelta == 0;
 
     /* segmentation header info */
+    s->segmentation.ignore_refmap = 0;
     if ((s->segmentation.enabled = get_bits1(&s->gb))) {
         if ((s->segmentation.update_map = get_bits1(&s->gb))) {
             for (i = 0; i < 7; i++)
                 s->prob.seg[i] = get_bits1(&s->gb) ?
                                  get_bits(&s->gb, 8) : 255;
-            if ((s->segmentation.temporal = get_bits1(&s->gb)))
+            if ((s->segmentation.temporal = get_bits1(&s->gb))) {
                 for (i = 0; i < 3; i++)
                     s->prob.segpred[i] = get_bits1(&s->gb) ?
                                          get_bits(&s->gb, 8) : 255;
+            }
+        }
+        if ((!s->segmentation.update_map || s->segmentation.temporal) &&
+            (w != s->frames[CUR_FRAME].tf.f->width ||
+             h != s->frames[CUR_FRAME].tf.f->height)) {
+            av_log(ctx, AV_LOG_WARNING,
+                   "Reference segmap (temp=%d,update=%d) enabled on size-change!\n",
+                   s->segmentation.temporal, s->segmentation.update_map);
+                s->segmentation.ignore_refmap = 1;
+            //return AVERROR_INVALIDDATA;
         }
 
         if (get_bits1(&s->gb)) {
             s->segmentation.absolute_vals = get_bits1(&s->gb);
             for (i = 0; i < 8; i++) {
                 if ((s->segmentation.feat[i].q_enabled = get_bits1(&s->gb)))
-                    s->segmentation.feat[i].q_val = get_bits_with_sign(&s->gb, 8);
+                    s->segmentation.feat[i].q_val = get_sbits_inv(&s->gb, 8);
                 if ((s->segmentation.feat[i].lf_enabled = get_bits1(&s->gb)))
-                    s->segmentation.feat[i].lf_val = get_bits_with_sign(&s->gb, 6);
+                    s->segmentation.feat[i].lf_val = get_sbits_inv(&s->gb, 6);
                 if ((s->segmentation.feat[i].ref_enabled = get_bits1(&s->gb)))
                     s->segmentation.feat[i].ref_val = get_bits(&s->gb, 2);
                 s->segmentation.feat[i].skip_enabled = get_bits1(&s->gb);
@@ -387,45 +785,49 @@ static int decode_frame_header(AVCodecContext *avctx,
             else
                 qyac = s->yac_qi + s->segmentation.feat[i].q_val;
         } else {
-            qyac = s->yac_qi;
+            qyac  = s->yac_qi;
         }
         qydc  = av_clip_uintp2(qyac + s->ydc_qdelta, 8);
         quvdc = av_clip_uintp2(qyac + s->uvdc_qdelta, 8);
         quvac = av_clip_uintp2(qyac + s->uvac_qdelta, 8);
         qyac  = av_clip_uintp2(qyac, 8);
 
-        s->segmentation.feat[i].qmul[0][0] = ff_vp9_dc_qlookup[qydc];
-        s->segmentation.feat[i].qmul[0][1] = ff_vp9_ac_qlookup[qyac];
-        s->segmentation.feat[i].qmul[1][0] = ff_vp9_dc_qlookup[quvdc];
-        s->segmentation.feat[i].qmul[1][1] = ff_vp9_ac_qlookup[quvac];
+        s->segmentation.feat[i].qmul[0][0] = vp9_dc_qlookup[s->bpp_index][qydc];
+        s->segmentation.feat[i].qmul[0][1] = vp9_ac_qlookup[s->bpp_index][qyac];
+        s->segmentation.feat[i].qmul[1][0] = vp9_dc_qlookup[s->bpp_index][quvdc];
+        s->segmentation.feat[i].qmul[1][1] = vp9_ac_qlookup[s->bpp_index][quvac];
 
         sh = s->filter.level >= 32;
         if (s->segmentation.feat[i].lf_enabled) {
             if (s->segmentation.absolute_vals)
-                lflvl = s->segmentation.feat[i].lf_val;
+                lflvl = av_clip_uintp2(s->segmentation.feat[i].lf_val, 6);
             else
-                lflvl = s->filter.level + s->segmentation.feat[i].lf_val;
+                lflvl = av_clip_uintp2(s->filter.level + s->segmentation.feat[i].lf_val, 6);
         } else {
-            lflvl = s->filter.level;
+            lflvl  = s->filter.level;
         }
-        s->segmentation.feat[i].lflvl[0][0] =
-        s->segmentation.feat[i].lflvl[0][1] =
-            av_clip_uintp2(lflvl + (s->lf_delta.ref[0] << sh), 6);
-        for (j = 1; j < 4; j++) {
-            s->segmentation.feat[i].lflvl[j][0] =
-                av_clip_uintp2(lflvl + ((s->lf_delta.ref[j] +
-                                         s->lf_delta.mode[0]) << sh), 6);
-            s->segmentation.feat[i].lflvl[j][1] =
-                av_clip_uintp2(lflvl + ((s->lf_delta.ref[j] +
-                                         s->lf_delta.mode[1]) << sh), 6);
+        if (s->lf_delta.enabled) {
+            s->segmentation.feat[i].lflvl[0][0] =
+            s->segmentation.feat[i].lflvl[0][1] =
+                av_clip_uintp2(lflvl + (s->lf_delta.ref[0] << sh), 6);
+            for (j = 1; j < 4; j++) {
+                s->segmentation.feat[i].lflvl[j][0] =
+                    av_clip_uintp2(lflvl + ((s->lf_delta.ref[j] +
+                                             s->lf_delta.mode[0]) * (1 << sh)), 6);
+                s->segmentation.feat[i].lflvl[j][1] =
+                    av_clip_uintp2(lflvl + ((s->lf_delta.ref[j] +
+                                             s->lf_delta.mode[1]) * (1 << sh)), 6);
+            }
+        } else {
+            memset(s->segmentation.feat[i].lflvl, lflvl,
+                   sizeof(s->segmentation.feat[i].lflvl));
         }
     }
 
     /* tiling info */
-    if ((ret = update_size(avctx, w, h)) < 0) {
-        av_log(avctx, AV_LOG_ERROR,
-               "Failed to initialize decoder for %dx%d\n", w, h);
-        return ret;
+    if ((res = update_size(ctx, w, h, fmt)) < 0) {
+        av_log(ctx, AV_LOG_ERROR, "Failed to initialize decoder for %dx%d @ %d\n", w, h, fmt);
+        return res;
     }
     for (s->tiling.log2_tile_cols = 0;
          (s->sb_cols >> s->tiling.log2_tile_cols) > 64;
@@ -439,56 +841,52 @@ static int decode_frame_header(AVCodecContext *avctx,
             break;
     }
     s->tiling.log2_tile_rows = decode012(&s->gb);
-    s->tiling.tile_rows      = 1 << s->tiling.log2_tile_rows;
+    s->tiling.tile_rows = 1 << s->tiling.log2_tile_rows;
     if (s->tiling.tile_cols != (1 << s->tiling.log2_tile_cols)) {
         s->tiling.tile_cols = 1 << s->tiling.log2_tile_cols;
-        s->c_b              = av_fast_realloc(s->c_b, &s->c_b_size,
-                                              sizeof(VP56RangeCoder) *
-                                              s->tiling.tile_cols);
+        s->c_b = av_fast_realloc(s->c_b, &s->c_b_size,
+                                 sizeof(VP56RangeCoder) * s->tiling.tile_cols);
         if (!s->c_b) {
-            av_log(avctx, AV_LOG_ERROR,
-                   "Ran out of memory during range coder init\n");
+            av_log(ctx, AV_LOG_ERROR, "Ran out of memory during range coder init\n");
             return AVERROR(ENOMEM);
         }
     }
 
     if (s->keyframe || s->errorres || s->intraonly) {
-        s->prob_ctx[0].p =
-        s->prob_ctx[1].p =
-        s->prob_ctx[2].p =
-        s->prob_ctx[3].p = ff_vp9_default_probs;
-        memcpy(s->prob_ctx[0].coef, ff_vp9_default_coef_probs,
-               sizeof(ff_vp9_default_coef_probs));
-        memcpy(s->prob_ctx[1].coef, ff_vp9_default_coef_probs,
-               sizeof(ff_vp9_default_coef_probs));
-        memcpy(s->prob_ctx[2].coef, ff_vp9_default_coef_probs,
-               sizeof(ff_vp9_default_coef_probs));
-        memcpy(s->prob_ctx[3].coef, ff_vp9_default_coef_probs,
-               sizeof(ff_vp9_default_coef_probs));
+        s->prob_ctx[0].p = s->prob_ctx[1].p = s->prob_ctx[2].p =
+                           s->prob_ctx[3].p = vp9_default_probs;
+        memcpy(s->prob_ctx[0].coef, vp9_default_coef_probs,
+               sizeof(vp9_default_coef_probs));
+        memcpy(s->prob_ctx[1].coef, vp9_default_coef_probs,
+               sizeof(vp9_default_coef_probs));
+        memcpy(s->prob_ctx[2].coef, vp9_default_coef_probs,
+               sizeof(vp9_default_coef_probs));
+        memcpy(s->prob_ctx[3].coef, vp9_default_coef_probs,
+               sizeof(vp9_default_coef_probs));
     }
 
     // next 16 bits is size of the rest of the header (arith-coded)
     size2 = get_bits(&s->gb, 16);
     data2 = align_get_bits(&s->gb);
     if (size2 > size - (data2 - data)) {
-        av_log(avctx, AV_LOG_ERROR, "Invalid compressed header size\n");
+        av_log(ctx, AV_LOG_ERROR, "Invalid compressed header size\n");
         return AVERROR_INVALIDDATA;
     }
     ff_vp56_init_range_decoder(&s->c, data2, size2);
     if (vp56_rac_get_prob_branchy(&s->c, 128)) { // marker bit
-        av_log(avctx, AV_LOG_ERROR, "Marker bit was set\n");
+        av_log(ctx, AV_LOG_ERROR, "Marker bit was set\n");
         return AVERROR_INVALIDDATA;
     }
 
-    if (s->keyframe || s->intraonly)
-        memset(s->counts.coef, 0,
-               sizeof(s->counts.coef) + sizeof(s->counts.eob));
-    else
+    if (s->keyframe || s->intraonly) {
+        memset(s->counts.coef, 0, sizeof(s->counts.coef));
+        memset(s->counts.eob,  0, sizeof(s->counts.eob));
+    } else {
         memset(&s->counts, 0, sizeof(s->counts));
-
-    /* FIXME is it faster to not copy here, but do it down in the fw updates
-     * as explicit copies if the fw update is missing (and skip the copy upon
-     * fw update)? */
+    }
+    // FIXME is it faster to not copy here, but do it down in the fw updates
+    // as explicit copies if the fw update is missing (and skip the copy upon
+    // fw update)?
     s->prob.p = s->prob_ctx[c].p;
 
     // txfm updates
@@ -529,10 +927,11 @@ static int decode_frame_header(AVCodecContext *avctx,
                             if (m >= 3 && l == 0) // dc only has 3 pt
                                 break;
                             for (n = 0; n < 3; n++) {
-                                if (vp56_rac_get_prob_branchy(&s->c, 252))
+                                if (vp56_rac_get_prob_branchy(&s->c, 252)) {
                                     p[n] = update_prob(&s->c, r[n]);
-                                else
+                                } else {
                                     p[n] = r[n];
+                                }
                             }
                             p[3] = 0;
                         }
@@ -617,8 +1016,7 @@ static int decode_frame_header(AVCodecContext *avctx,
                 for (k = 0; k < 3; k++)
                     if (vp56_rac_get_prob_branchy(&s->c, 252))
                         s->prob.p.partition[3 - i][j][k] =
-                            update_prob(&s->c,
-                                        s->prob.p.partition[3 - i][j][k]);
+                            update_prob(&s->c, s->prob.p.partition[3 - i][j][k]);
 
         // mv fields don't use the update_prob subexp model for some reason
         for (i = 0; i < 3; i++)
@@ -627,8 +1025,7 @@ static int decode_frame_header(AVCodecContext *avctx,
 
         for (i = 0; i < 2; i++) {
             if (vp56_rac_get_prob_branchy(&s->c, 252))
-                s->prob.p.mv_comp[i].sign =
-                    (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
+                s->prob.p.mv_comp[i].sign = (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
 
             for (j = 0; j < 10; j++)
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
@@ -636,8 +1033,7 @@ static int decode_frame_header(AVCodecContext *avctx,
                         (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
 
             if (vp56_rac_get_prob_branchy(&s->c, 252))
-                s->prob.p.mv_comp[i].class0 =
-                    (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
+                s->prob.p.mv_comp[i].class0 = (vp8_rac_get_uint(&s->c, 7) << 1) | 1;
 
             for (j = 0; j < 10; j++)
                 if (vp56_rac_get_prob_branchy(&s->c, 252))
@@ -674,640 +1070,3293 @@ static int decode_frame_header(AVCodecContext *avctx,
     return (data2 - data) + size2;
 }
 
-static int decode_subblock(AVCodecContext *avctx, int row, int col,
-                           VP9Filter *lflvl,
-                           ptrdiff_t yoff, ptrdiff_t uvoff, enum BlockLevel bl)
+static av_always_inline void clamp_mv(VP56mv *dst, const VP56mv *src,
+                                      VP9Context *s)
 {
-    VP9Context *s = avctx->priv_data;
-    int c = ((s->above_partition_ctx[col]       >> (3 - bl)) & 1) |
-            (((s->left_partition_ctx[row & 0x7] >> (3 - bl)) & 1) << 1);
-    int ret;
-    const uint8_t *p = s->keyframe ? ff_vp9_default_kf_partition_probs[bl][c]
-                                   : s->prob.p.partition[bl][c];
-    enum BlockPartition bp;
-    ptrdiff_t hbs = 4 >> bl;
+    dst->x = av_clip(src->x, s->min_mv.x, s->max_mv.x);
+    dst->y = av_clip(src->y, s->min_mv.y, s->max_mv.y);
+}
 
-    if (bl == BL_8X8) {
-        bp  = vp8_rac_get_tree(&s->c, ff_vp9_partition_tree, p);
-        ret = ff_vp9_decode_block(avctx, row, col, lflvl, yoff, uvoff, bl, bp);
-    } else if (col + hbs < s->cols) {
-        if (row + hbs < s->rows) {
-            bp = vp8_rac_get_tree(&s->c, ff_vp9_partition_tree, p);
-            switch (bp) {
-            case PARTITION_NONE:
-                ret = ff_vp9_decode_block(avctx, row, col, lflvl, yoff, uvoff,
-                                          bl, bp);
-                break;
-            case PARTITION_H:
-                ret = ff_vp9_decode_block(avctx, row, col, lflvl, yoff, uvoff,
-                                          bl, bp);
-                if (!ret) {
-                    yoff  += hbs * 8 * s->cur_frame->linesize[0];
-                    uvoff += hbs * 4 * s->cur_frame->linesize[1];
-                    ret    = ff_vp9_decode_block(avctx, row + hbs, col, lflvl,
-                                                 yoff, uvoff, bl, bp);
-                }
-                break;
-            case PARTITION_V:
-                ret = ff_vp9_decode_block(avctx, row, col, lflvl, yoff, uvoff,
-                                          bl, bp);
-                if (!ret) {
-                    yoff  += hbs * 8;
-                    uvoff += hbs * 4;
-                    ret    = ff_vp9_decode_block(avctx, row, col + hbs, lflvl,
-                                                 yoff, uvoff, bl, bp);
-                }
-                break;
-            case PARTITION_SPLIT:
-                ret = decode_subblock(avctx, row, col, lflvl,
-                                      yoff, uvoff, bl + 1);
-                if (!ret) {
-                    ret = decode_subblock(avctx, row, col + hbs, lflvl,
-                                          yoff + 8 * hbs, uvoff + 4 * hbs,
-                                          bl + 1);
-                    if (!ret) {
-                        yoff  += hbs * 8 * s->cur_frame->linesize[0];
-                        uvoff += hbs * 4 * s->cur_frame->linesize[1];
-                        ret    = decode_subblock(avctx, row + hbs, col, lflvl,
-                                                 yoff, uvoff, bl + 1);
-                        if (!ret) {
-                            ret = decode_subblock(avctx, row + hbs, col + hbs,
-                                                  lflvl, yoff + 8 * hbs,
-                                                  uvoff + 4 * hbs, bl + 1);
-                        }
-                    }
-                }
-                break;
-            default:
-                av_log(avctx, AV_LOG_ERROR, "Unexpected partition %d.", bp);
-                return AVERROR_INVALIDDATA;
+static void find_ref_mvs(VP9Context *s,
+                         VP56mv *pmv, int ref, int z, int idx, int sb)
+{
+    static const int8_t mv_ref_blk_off[N_BS_SIZES][8][2] = {
+        [BS_64x64] = {{  3, -1 }, { -1,  3 }, {  4, -1 }, { -1,  4 },
+                      { -1, -1 }, {  0, -1 }, { -1,  0 }, {  6, -1 }},
+        [BS_64x32] = {{  0, -1 }, { -1,  0 }, {  4, -1 }, { -1,  2 },
+                      { -1, -1 }, {  0, -3 }, { -3,  0 }, {  2, -1 }},
+        [BS_32x64] = {{ -1,  0 }, {  0, -1 }, { -1,  4 }, {  2, -1 },
+                      { -1, -1 }, { -3,  0 }, {  0, -3 }, { -1,  2 }},
+        [BS_32x32] = {{  1, -1 }, { -1,  1 }, {  2, -1 }, { -1,  2 },
+                      { -1, -1 }, {  0, -3 }, { -3,  0 }, { -3, -3 }},
+        [BS_32x16] = {{  0, -1 }, { -1,  0 }, {  2, -1 }, { -1, -1 },
+                      { -1,  1 }, {  0, -3 }, { -3,  0 }, { -3, -3 }},
+        [BS_16x32] = {{ -1,  0 }, {  0, -1 }, { -1,  2 }, { -1, -1 },
+                      {  1, -1 }, { -3,  0 }, {  0, -3 }, { -3, -3 }},
+        [BS_16x16] = {{  0, -1 }, { -1,  0 }, {  1, -1 }, { -1,  1 },
+                      { -1, -1 }, {  0, -3 }, { -3,  0 }, { -3, -3 }},
+        [BS_16x8]  = {{  0, -1 }, { -1,  0 }, {  1, -1 }, { -1, -1 },
+                      {  0, -2 }, { -2,  0 }, { -2, -1 }, { -1, -2 }},
+        [BS_8x16]  = {{ -1,  0 }, {  0, -1 }, { -1,  1 }, { -1, -1 },
+                      { -2,  0 }, {  0, -2 }, { -1, -2 }, { -2, -1 }},
+        [BS_8x8]   = {{  0, -1 }, { -1,  0 }, { -1, -1 }, {  0, -2 },
+                      { -2,  0 }, { -1, -2 }, { -2, -1 }, { -2, -2 }},
+        [BS_8x4]   = {{  0, -1 }, { -1,  0 }, { -1, -1 }, {  0, -2 },
+                      { -2,  0 }, { -1, -2 }, { -2, -1 }, { -2, -2 }},
+        [BS_4x8]   = {{  0, -1 }, { -1,  0 }, { -1, -1 }, {  0, -2 },
+                      { -2,  0 }, { -1, -2 }, { -2, -1 }, { -2, -2 }},
+        [BS_4x4]   = {{  0, -1 }, { -1,  0 }, { -1, -1 }, {  0, -2 },
+                      { -2,  0 }, { -1, -2 }, { -2, -1 }, { -2, -2 }},
+    };
+    VP9Block *b = s->b;
+    int row = s->row, col = s->col, row7 = s->row7;
+    const int8_t (*p)[2] = mv_ref_blk_off[b->bs];
+#define INVALID_MV 0x80008000U
+    uint32_t mem = INVALID_MV, mem_sub8x8 = INVALID_MV;
+    int i;
+
+#define RETURN_DIRECT_MV(mv) \
+    do { \
+        uint32_t m = AV_RN32A(&mv); \
+        if (!idx) { \
+            AV_WN32A(pmv, m); \
+            return; \
+        } else if (mem == INVALID_MV) { \
+            mem = m; \
+        } else if (m != mem) { \
+            AV_WN32A(pmv, m); \
+            return; \
+        } \
+    } while (0)
+
+    if (sb >= 0) {
+        if (sb == 2 || sb == 1) {
+            RETURN_DIRECT_MV(b->mv[0][z]);
+        } else if (sb == 3) {
+            RETURN_DIRECT_MV(b->mv[2][z]);
+            RETURN_DIRECT_MV(b->mv[1][z]);
+            RETURN_DIRECT_MV(b->mv[0][z]);
+        }
+
+#define RETURN_MV(mv) \
+    do { \
+        if (sb > 0) { \
+            VP56mv tmp; \
+            uint32_t m; \
+            av_assert2(idx == 1); \
+            av_assert2(mem != INVALID_MV); \
+            if (mem_sub8x8 == INVALID_MV) { \
+                clamp_mv(&tmp, &mv, s); \
+                m = AV_RN32A(&tmp); \
+                if (m != mem) { \
+                    AV_WN32A(pmv, m); \
+                    return; \
+                } \
+                mem_sub8x8 = AV_RN32A(&mv); \
+            } else if (mem_sub8x8 != AV_RN32A(&mv)) { \
+                clamp_mv(&tmp, &mv, s); \
+                m = AV_RN32A(&tmp); \
+                if (m != mem) { \
+                    AV_WN32A(pmv, m); \
+                } else { \
+                    /* BUG I'm pretty sure this isn't the intention */ \
+                    AV_WN32A(pmv, 0); \
+                } \
+                return; \
+            } \
+        } else { \
+            uint32_t m = AV_RN32A(&mv); \
+            if (!idx) { \
+                clamp_mv(pmv, &mv, s); \
+                return; \
+            } else if (mem == INVALID_MV) { \
+                mem = m; \
+            } else if (m != mem) { \
+                clamp_mv(pmv, &mv, s); \
+                return; \
+            } \
+        } \
+    } while (0)
+
+        if (row > 0) {
+            struct VP9mvrefPair *mv = &s->frames[CUR_FRAME].mv[(row - 1) * s->sb_cols * 8 + col];
+            if (mv->ref[0] == ref) {
+                RETURN_MV(s->above_mv_ctx[2 * col + (sb & 1)][0]);
+            } else if (mv->ref[1] == ref) {
+                RETURN_MV(s->above_mv_ctx[2 * col + (sb & 1)][1]);
             }
-        } else if (vp56_rac_get_prob_branchy(&s->c, p[1])) {
-            bp  = PARTITION_SPLIT;
-            ret = decode_subblock(avctx, row, col, lflvl, yoff, uvoff, bl + 1);
-            if (!ret)
-                ret = decode_subblock(avctx, row, col + hbs, lflvl,
-                                      yoff + 8 * hbs, uvoff + 4 * hbs, bl + 1);
-        } else {
-            bp  = PARTITION_H;
-            ret = ff_vp9_decode_block(avctx, row, col, lflvl, yoff, uvoff,
-                                      bl, bp);
         }
-    } else if (row + hbs < s->rows) {
-        if (vp56_rac_get_prob_branchy(&s->c, p[2])) {
-            bp  = PARTITION_SPLIT;
-            ret = decode_subblock(avctx, row, col, lflvl, yoff, uvoff, bl + 1);
-            if (!ret) {
-                yoff  += hbs * 8 * s->cur_frame->linesize[0];
-                uvoff += hbs * 4 * s->cur_frame->linesize[1];
-                ret    = decode_subblock(avctx, row + hbs, col, lflvl,
-                                         yoff, uvoff, bl + 1);
+        if (col > s->tiling.tile_col_start) {
+            struct VP9mvrefPair *mv = &s->frames[CUR_FRAME].mv[row * s->sb_cols * 8 + col - 1];
+            if (mv->ref[0] == ref) {
+                RETURN_MV(s->left_mv_ctx[2 * row7 + (sb >> 1)][0]);
+            } else if (mv->ref[1] == ref) {
+                RETURN_MV(s->left_mv_ctx[2 * row7 + (sb >> 1)][1]);
             }
-        } else {
-            bp  = PARTITION_V;
-            ret = ff_vp9_decode_block(avctx, row, col, lflvl, yoff, uvoff,
-                                      bl, bp);
         }
+        i = 2;
     } else {
-        bp  = PARTITION_SPLIT;
-        ret = decode_subblock(avctx, row, col, lflvl, yoff, uvoff, bl + 1);
+        i = 0;
     }
-    s->counts.partition[bl][c][bp]++;
-
-    return ret;
-}
-
-static void loopfilter_subblock(AVCodecContext *avctx, VP9Filter *lflvl,
-                                int row, int col,
-                                ptrdiff_t yoff, ptrdiff_t uvoff)
-{
-    VP9Context *s = avctx->priv_data;
-    uint8_t *dst   = s->cur_frame->data[0] + yoff, *lvl = lflvl->level;
-    ptrdiff_t ls_y = s->cur_frame->linesize[0], ls_uv = s->cur_frame->linesize[1];
-    int y, x, p;
-
-    /* FIXME: In how far can we interleave the v/h loopfilter calls? E.g.
-     * if you think of them as acting on a 8x8 block max, we can interleave
-     * each v/h within the single x loop, but that only works if we work on
-     * 8 pixel blocks, and we won't always do that (we want at least 16px
-     * to use SSE2 optimizations, perhaps 32 for AVX2). */
-
-    // filter edges between columns, Y plane (e.g. block1 | block2)
-    for (y = 0; y < 8; y += 2, dst += 16 * ls_y, lvl += 16) {
-        uint8_t *ptr = dst, *l = lvl, *hmask1 = lflvl->mask[0][0][y];
-        uint8_t *hmask2 = lflvl->mask[0][0][y + 1];
-        unsigned hm1 = hmask1[0] | hmask1[1] | hmask1[2], hm13 = hmask1[3];
-        unsigned hm2 = hmask2[1] | hmask2[2], hm23 = hmask2[3];
-        unsigned hm  = hm1 | hm2 | hm13 | hm23;
 
-        for (x = 1; hm & ~(x - 1); x <<= 1, ptr += 8, l++) {
-            if (hm1 & x) {
-                int L = *l, H = L >> 4;
-                int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+    // previously coded MVs in this neighbourhood, using same reference frame
+    for (; i < 8; i++) {
+        int c = p[i][0] + col, r = p[i][1] + row;
 
-                if (col || x > 1) {
-                    if (hmask1[0] & x) {
-                        if (hmask2[0] & x) {
-                            av_assert2(l[8] == L);
-                            s->dsp.loop_filter_16[0](ptr, ls_y, E, I, H);
-                        } else {
-                            s->dsp.loop_filter_8[2][0](ptr, ls_y, E, I, H);
-                        }
-                    } else if (hm2 & x) {
-                        L  = l[8];
-                        H |= (L >> 4) << 8;
-                        E |= s->filter.mblim_lut[L] << 8;
-                        I |= s->filter.lim_lut[L] << 8;
-                        s->dsp.loop_filter_mix2[!!(hmask1[1] & x)]
-                                               [!!(hmask2[1] & x)]
-                                               [0](ptr, ls_y, E, I, H);
-                    } else {
-                        s->dsp.loop_filter_8[!!(hmask1[1] & x)]
-                                            [0](ptr, ls_y, E, I, H);
-                    }
-                }
-            } else if (hm2 & x) {
-                int L = l[8], H = L >> 4;
-                int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+        if (c >= s->tiling.tile_col_start && c < s->cols && r >= 0 && r < s->rows) {
+            struct VP9mvrefPair *mv = &s->frames[CUR_FRAME].mv[r * s->sb_cols * 8 + c];
 
-                if (col || x > 1) {
-                    s->dsp.loop_filter_8[!!(hmask2[1] & x)]
-                                        [0](ptr + 8 * ls_y, ls_y, E, I, H);
-                }
+            if (mv->ref[0] == ref) {
+                RETURN_MV(mv->mv[0]);
+            } else if (mv->ref[1] == ref) {
+                RETURN_MV(mv->mv[1]);
             }
-            if (hm13 & x) {
-                int L = *l, H = L >> 4;
-                int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+        }
+    }
 
-                if (hm23 & x) {
-                    L  = l[8];
-                    H |= (L >> 4) << 8;
-                    E |= s->filter.mblim_lut[L] << 8;
-                    I |= s->filter.lim_lut[L] << 8;
-                    s->dsp.loop_filter_mix2[0][0][0](ptr + 4, ls_y, E, I, H);
-                } else {
-                    s->dsp.loop_filter_8[0][0](ptr + 4, ls_y, E, I, H);
-                }
-            } else if (hm23 & x) {
-                int L = l[8], H = L >> 4;
-                int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+    // MV at this position in previous frame, using same reference frame
+    if (s->use_last_frame_mvs) {
+        struct VP9mvrefPair *mv = &s->frames[REF_FRAME_MVPAIR].mv[row * s->sb_cols * 8 + col];
 
-                s->dsp.loop_filter_8[0][0](ptr + 8 * ls_y + 4, ls_y, E, I, H);
-            }
+        if (!s->frames[REF_FRAME_MVPAIR].uses_2pass)
+            ff_thread_await_progress(&s->frames[REF_FRAME_MVPAIR].tf, row >> 3, 0);
+        if (mv->ref[0] == ref) {
+            RETURN_MV(mv->mv[0]);
+        } else if (mv->ref[1] == ref) {
+            RETURN_MV(mv->mv[1]);
         }
     }
 
-    //                                          block1
-    // filter edges between rows, Y plane (e.g. ------)
-    //                                          block2
-    dst = s->cur_frame->data[0] + yoff;
-    lvl = lflvl->level;
-    for (y = 0; y < 8; y++, dst += 8 * ls_y, lvl += 8) {
-        uint8_t *ptr = dst, *l = lvl, *vmask = lflvl->mask[0][1][y];
-        unsigned vm = vmask[0] | vmask[1] | vmask[2], vm3 = vmask[3];
+#define RETURN_SCALE_MV(mv, scale) \
+    do { \
+        if (scale) { \
+            VP56mv mv_temp = { -mv.x, -mv.y }; \
+            RETURN_MV(mv_temp); \
+        } else { \
+            RETURN_MV(mv); \
+        } \
+    } while (0)
 
-        for (x = 1; vm & ~(x - 1); x <<= 2, ptr += 16, l += 2) {
-            if (row || y) {
-                if (vm & x) {
-                    int L = *l, H = L >> 4;
-                    int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+    // previously coded MVs in this neighbourhood, using different reference frame
+    for (i = 0; i < 8; i++) {
+        int c = p[i][0] + col, r = p[i][1] + row;
 
-                    if (vmask[0] & x) {
-                        if (vmask[0] & (x << 1)) {
-                            av_assert2(l[1] == L);
-                            s->dsp.loop_filter_16[1](ptr, ls_y, E, I, H);
-                        } else {
-                            s->dsp.loop_filter_8[2][1](ptr, ls_y, E, I, H);
-                        }
-                    } else if (vm & (x << 1)) {
-                        L  = l[1];
-                        H |= (L >> 4) << 8;
-                        E |= s->filter.mblim_lut[L] << 8;
-                        I |= s->filter.lim_lut[L] << 8;
-                        s->dsp.loop_filter_mix2[!!(vmask[1] &  x)]
-                                               [!!(vmask[1] & (x << 1))]
-                                               [1](ptr, ls_y, E, I, H);
-                    } else {
-                        s->dsp.loop_filter_8[!!(vmask[1] & x)]
-                                            [1](ptr, ls_y, E, I, H);
-                    }
-                } else if (vm & (x << 1)) {
-                    int L = l[1], H = L >> 4;
-                    int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+        if (c >= s->tiling.tile_col_start && c < s->cols && r >= 0 && r < s->rows) {
+            struct VP9mvrefPair *mv = &s->frames[CUR_FRAME].mv[r * s->sb_cols * 8 + c];
 
-                    s->dsp.loop_filter_8[!!(vmask[1] & (x << 1))]
-                                        [1](ptr + 8, ls_y, E, I, H);
-                }
+            if (mv->ref[0] != ref && mv->ref[0] >= 0) {
+                RETURN_SCALE_MV(mv->mv[0], s->signbias[mv->ref[0]] != s->signbias[ref]);
             }
-            if (vm3 & x) {
-                int L = *l, H = L >> 4;
-                int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
-
-                if (vm3 & (x << 1)) {
-                    L  = l[1];
-                    H |= (L >> 4) << 8;
-                    E |= s->filter.mblim_lut[L] << 8;
-                    I |= s->filter.lim_lut[L] << 8;
-                    s->dsp.loop_filter_mix2[0][0][1](ptr + ls_y * 4, ls_y, E, I, H);
-                } else {
-                    s->dsp.loop_filter_8[0][1](ptr + ls_y * 4, ls_y, E, I, H);
-                }
-            } else if (vm3 & (x << 1)) {
-                int L = l[1], H = L >> 4;
-                int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
-
-                s->dsp.loop_filter_8[0][1](ptr + ls_y * 4 + 8, ls_y, E, I, H);
+            if (mv->ref[1] != ref && mv->ref[1] >= 0 &&
+                // BUG - libvpx has this condition regardless of whether
+                // we used the first ref MV and pre-scaling
+                AV_RN32A(&mv->mv[0]) != AV_RN32A(&mv->mv[1])) {
+                RETURN_SCALE_MV(mv->mv[1], s->signbias[mv->ref[1]] != s->signbias[ref]);
             }
         }
     }
 
-    // same principle but for U/V planes
-    for (p = 0; p < 2; p++) {
-        lvl = lflvl->level;
-        dst = s->cur_frame->data[1 + p] + uvoff;
-        for (y = 0; y < 8; y += 4, dst += 16 * ls_uv, lvl += 32) {
-            uint8_t *ptr = dst, *l = lvl, *hmask1 = lflvl->mask[1][0][y];
-            uint8_t *hmask2 = lflvl->mask[1][0][y + 2];
-            unsigned hm1 = hmask1[0] | hmask1[1] | hmask1[2];
-            unsigned hm2 = hmask2[1] | hmask2[2], hm = hm1 | hm2;
-
-            for (x = 1; hm & ~(x - 1); x <<= 1, ptr += 4) {
-                if (col || x > 1) {
-                    if (hm1 & x) {
-                        int L = *l, H = L >> 4;
-                        int E = s->filter.mblim_lut[L];
-                        int I = s->filter.lim_lut[L];
-
-                        if (hmask1[0] & x) {
-                            if (hmask2[0] & x) {
-                                av_assert2(l[16] == L);
-                                s->dsp.loop_filter_16[0](ptr, ls_uv, E, I, H);
-                            } else {
-                                s->dsp.loop_filter_8[2][0](ptr, ls_uv, E, I, H);
-                            }
-                        } else if (hm2 & x) {
-                            L  = l[16];
-                            H |= (L >> 4) << 8;
-                            E |= s->filter.mblim_lut[L] << 8;
-                            I |= s->filter.lim_lut[L] << 8;
-                            s->dsp.loop_filter_mix2[!!(hmask1[1] & x)]
-                                                   [!!(hmask2[1] & x)]
-                                                   [0](ptr, ls_uv, E, I, H);
-                        } else {
-                            s->dsp.loop_filter_8[!!(hmask1[1] & x)]
-                                                [0](ptr, ls_uv, E, I, H);
-                        }
-                    } else if (hm2 & x) {
-                        int L = l[16], H = L >> 4;
-                        int E = s->filter.mblim_lut[L];
-                        int I = s->filter.lim_lut[L];
+    // MV at this position in previous frame, using different reference frame
+    if (s->use_last_frame_mvs) {
+        struct VP9mvrefPair *mv = &s->frames[REF_FRAME_MVPAIR].mv[row * s->sb_cols * 8 + col];
 
-                        s->dsp.loop_filter_8[!!(hmask2[1] & x)]
-                                            [0](ptr + 8 * ls_uv, ls_uv, E, I, H);
-                    }
-                }
-                if (x & 0xAA)
-                    l += 2;
-            }
+        // no need to await_progress, because we already did that above
+        if (mv->ref[0] != ref && mv->ref[0] >= 0) {
+            RETURN_SCALE_MV(mv->mv[0], s->signbias[mv->ref[0]] != s->signbias[ref]);
         }
-        lvl = lflvl->level;
-        dst = s->cur_frame->data[1 + p] + uvoff;
-        for (y = 0; y < 8; y++, dst += 4 * ls_uv) {
-            uint8_t *ptr = dst, *l = lvl, *vmask = lflvl->mask[1][1][y];
-            unsigned vm = vmask[0] | vmask[1] | vmask[2];
+        if (mv->ref[1] != ref && mv->ref[1] >= 0 &&
+            // BUG - libvpx has this condition regardless of whether
+            // we used the first ref MV and pre-scaling
+            AV_RN32A(&mv->mv[0]) != AV_RN32A(&mv->mv[1])) {
+            RETURN_SCALE_MV(mv->mv[1], s->signbias[mv->ref[1]] != s->signbias[ref]);
+        }
+    }
 
-            for (x = 1; vm & ~(x - 1); x <<= 4, ptr += 16, l += 4) {
-                if (row || y) {
-                    if (vm & x) {
-                        int L = *l, H = L >> 4;
-                        int E = s->filter.mblim_lut[L];
-                        int I = s->filter.lim_lut[L];
+    AV_ZERO32(pmv);
+    clamp_mv(pmv, pmv, s);
+#undef INVALID_MV
+#undef RETURN_MV
+#undef RETURN_SCALE_MV
+}
 
-                        if (vmask[0] & x) {
-                            if (vmask[0] & (x << 2)) {
-                                av_assert2(l[2] == L);
-                                s->dsp.loop_filter_16[1](ptr, ls_uv, E, I, H);
-                            } else {
-                                s->dsp.loop_filter_8[2][1](ptr, ls_uv, E, I, H);
-                            }
-                        } else if (vm & (x << 2)) {
-                            L  = l[2];
-                            H |= (L >> 4) << 8;
-                            E |= s->filter.mblim_lut[L] << 8;
-                            I |= s->filter.lim_lut[L] << 8;
-                            s->dsp.loop_filter_mix2[!!(vmask[1] &  x)]
-                                                   [!!(vmask[1] & (x << 2))]
-                                                   [1](ptr, ls_uv, E, I, H);
-                        } else {
-                            s->dsp.loop_filter_8[!!(vmask[1] & x)]
-                                                [1](ptr, ls_uv, E, I, H);
-                        }
-                    } else if (vm & (x << 2)) {
-                        int L = l[2], H = L >> 4;
-                        int E = s->filter.mblim_lut[L];
-                        int I = s->filter.lim_lut[L];
+static av_always_inline int read_mv_component(VP9Context *s, int idx, int hp)
+{
+    int bit, sign = vp56_rac_get_prob(&s->c, s->prob.p.mv_comp[idx].sign);
+    int n, c = vp8_rac_get_tree(&s->c, vp9_mv_class_tree,
+                                s->prob.p.mv_comp[idx].classes);
 
-                        s->dsp.loop_filter_8[!!(vmask[1] & (x << 2))]
-                                            [1](ptr + 8, ls_uv, E, I, H);
-                    }
-                }
-            }
-            if (y & 1)
-                lvl += 16;
+    s->counts.mv_comp[idx].sign[sign]++;
+    s->counts.mv_comp[idx].classes[c]++;
+    if (c) {
+        int m;
+
+        for (n = 0, m = 0; m < c; m++) {
+            bit = vp56_rac_get_prob(&s->c, s->prob.p.mv_comp[idx].bits[m]);
+            n |= bit << m;
+            s->counts.mv_comp[idx].bits[m][bit]++;
+        }
+        n <<= 3;
+        bit = vp8_rac_get_tree(&s->c, vp9_mv_fp_tree, s->prob.p.mv_comp[idx].fp);
+        n |= bit << 1;
+        s->counts.mv_comp[idx].fp[bit]++;
+        if (hp) {
+            bit = vp56_rac_get_prob(&s->c, s->prob.p.mv_comp[idx].hp);
+            s->counts.mv_comp[idx].hp[bit]++;
+            n |= bit;
+        } else {
+            n |= 1;
+            // bug in libvpx - we count for bw entropy purposes even if the
+            // bit wasn't coded
+            s->counts.mv_comp[idx].hp[1]++;
+        }
+        n += 8 << c;
+    } else {
+        n = vp56_rac_get_prob(&s->c, s->prob.p.mv_comp[idx].class0);
+        s->counts.mv_comp[idx].class0[n]++;
+        bit = vp8_rac_get_tree(&s->c, vp9_mv_fp_tree,
+                               s->prob.p.mv_comp[idx].class0_fp[n]);
+        s->counts.mv_comp[idx].class0_fp[n][bit]++;
+        n = (n << 3) | (bit << 1);
+        if (hp) {
+            bit = vp56_rac_get_prob(&s->c, s->prob.p.mv_comp[idx].class0_hp);
+            s->counts.mv_comp[idx].class0_hp[bit]++;
+            n |= bit;
+        } else {
+            n |= 1;
+            // bug in libvpx - we count for bw entropy purposes even if the
+            // bit wasn't coded
+            s->counts.mv_comp[idx].class0_hp[1]++;
         }
     }
-}
 
-static void set_tile_offset(int *start, int *end, int idx, int log2_n, int n)
-{
-    int sb_start =  (idx      * n) >> log2_n;
-    int sb_end   = ((idx + 1) * n) >> log2_n;
-    *start = FFMIN(sb_start, n) << 3;
-    *end   = FFMIN(sb_end,   n) << 3;
+    return sign ? -(n + 1) : (n + 1);
 }
 
-static int vp9_decode_frame(AVCodecContext *avctx, AVFrame *frame,
-                            int *got_frame, const uint8_t *data, int size)
+static void fill_mv(VP9Context *s,
+                    VP56mv *mv, int mode, int sb)
 {
-    VP9Context *s = avctx->priv_data;
-    int ret, tile_row, tile_col, i, ref = -1, row, col;
-    ptrdiff_t yoff = 0, uvoff = 0;
-
-    ret = decode_frame_header(avctx, data, size, &ref);
-    if (ret < 0) {
-        return ret;
-    } else if (!ret) {
-        if (!s->refs[ref]->buf[0]) {
-            av_log(avctx, AV_LOG_ERROR,
-                   "Requested reference %d not available\n", ref);
-            return AVERROR_INVALIDDATA;
-        }
+    VP9Block *b = s->b;
 
-        ret = av_frame_ref(frame, s->refs[ref]);
-        if (ret < 0)
-            return ret;
-        *got_frame = 1;
-        return 0;
-    }
-    data += ret;
-    size -= ret;
+    if (mode == ZEROMV) {
+        AV_ZERO64(mv);
+    } else {
+        int hp;
 
-    s->cur_frame = frame;
+        // FIXME cache this value and reuse for other subblocks
+        find_ref_mvs(s, &mv[0], b->ref[0], 0, mode == NEARMV,
+                     mode == NEWMV ? -1 : sb);
+        // FIXME maybe move this code into find_ref_mvs()
+        if ((mode == NEWMV || sb == -1) &&
+            !(hp = s->highprecisionmvs && abs(mv[0].x) < 64 && abs(mv[0].y) < 64)) {
+            if (mv[0].y & 1) {
+                if (mv[0].y < 0)
+                    mv[0].y++;
+                else
+                    mv[0].y--;
+            }
+            if (mv[0].x & 1) {
+                if (mv[0].x < 0)
+                    mv[0].x++;
+                else
+                    mv[0].x--;
+            }
+        }
+        if (mode == NEWMV) {
+            enum MVJoint j = vp8_rac_get_tree(&s->c, vp9_mv_joint_tree,
+                                              s->prob.p.mv_joint);
 
-    av_frame_unref(s->cur_frame);
-    if ((ret = ff_get_buffer(avctx, s->cur_frame,
-                             s->refreshrefmask ? AV_GET_BUFFER_FLAG_REF : 0)) < 0)
-        return ret;
-    s->cur_frame->key_frame = s->keyframe;
-    s->cur_frame->pict_type = s->keyframe ? AV_PICTURE_TYPE_I
-                                          : AV_PICTURE_TYPE_P;
+            s->counts.mv_joint[j]++;
+            if (j >= MV_JOINT_V)
+                mv[0].y += read_mv_component(s, 0, hp);
+            if (j & 1)
+                mv[0].x += read_mv_component(s, 1, hp);
+        }
 
-    if (s->fullrange)
-        avctx->color_range = AVCOL_RANGE_JPEG;
-    else
-        avctx->color_range = AVCOL_RANGE_MPEG;
+        if (b->comp) {
+            // FIXME cache this value and reuse for other subblocks
+            find_ref_mvs(s, &mv[1], b->ref[1], 1, mode == NEARMV,
+                         mode == NEWMV ? -1 : sb);
+            if ((mode == NEWMV || sb == -1) &&
+                !(hp = s->highprecisionmvs && abs(mv[1].x) < 64 && abs(mv[1].y) < 64)) {
+                if (mv[1].y & 1) {
+                    if (mv[1].y < 0)
+                        mv[1].y++;
+                    else
+                        mv[1].y--;
+                }
+                if (mv[1].x & 1) {
+                    if (mv[1].x < 0)
+                        mv[1].x++;
+                    else
+                        mv[1].x--;
+                }
+            }
+            if (mode == NEWMV) {
+                enum MVJoint j = vp8_rac_get_tree(&s->c, vp9_mv_joint_tree,
+                                                  s->prob.p.mv_joint);
 
-    switch (s->colorspace) {
-    case 1: avctx->colorspace = AVCOL_SPC_BT470BG; break;
-    case 2: avctx->colorspace = AVCOL_SPC_BT709; break;
-    case 3: avctx->colorspace = AVCOL_SPC_SMPTE170M; break;
-    case 4: avctx->colorspace = AVCOL_SPC_SMPTE240M; break;
+                s->counts.mv_joint[j]++;
+                if (j >= MV_JOINT_V)
+                    mv[1].y += read_mv_component(s, 0, hp);
+                if (j & 1)
+                    mv[1].x += read_mv_component(s, 1, hp);
+            }
+        }
     }
+}
 
-    // main tile decode loop
-    memset(s->above_partition_ctx, 0, s->cols);
-    memset(s->above_skip_ctx, 0, s->cols);
-    if (s->keyframe || s->intraonly)
-        memset(s->above_mode_ctx, DC_PRED, s->cols * 2);
-    else
-        memset(s->above_mode_ctx, NEARESTMV, s->cols);
-    memset(s->above_y_nnz_ctx, 0, s->sb_cols * 16);
-    memset(s->above_uv_nnz_ctx[0], 0, s->sb_cols * 8);
-    memset(s->above_uv_nnz_ctx[1], 0, s->sb_cols * 8);
-    memset(s->above_segpred_ctx, 0, s->cols);
-    for (tile_row = 0; tile_row < s->tiling.tile_rows; tile_row++) {
-        set_tile_offset(&s->tiling.tile_row_start, &s->tiling.tile_row_end,
-                        tile_row, s->tiling.log2_tile_rows, s->sb_rows);
-        for (tile_col = 0; tile_col < s->tiling.tile_cols; tile_col++) {
-            int64_t tile_size;
-
-            if (tile_col == s->tiling.tile_cols - 1 &&
-                tile_row == s->tiling.tile_rows - 1) {
-                tile_size = size;
+static av_always_inline void setctx_2d(uint8_t *ptr, int w, int h,
+                                       ptrdiff_t stride, int v)
+{
+    switch (w) {
+    case 1:
+        do {
+            *ptr = v;
+            ptr += stride;
+        } while (--h);
+        break;
+    case 2: {
+        int v16 = v * 0x0101;
+        do {
+            AV_WN16A(ptr, v16);
+            ptr += stride;
+        } while (--h);
+        break;
+    }
+    case 4: {
+        uint32_t v32 = v * 0x01010101;
+        do {
+            AV_WN32A(ptr, v32);
+            ptr += stride;
+        } while (--h);
+        break;
+    }
+    case 8: {
+#if HAVE_FAST_64BIT
+        uint64_t v64 = v * 0x0101010101010101ULL;
+        do {
+            AV_WN64A(ptr, v64);
+            ptr += stride;
+        } while (--h);
+#else
+        uint32_t v32 = v * 0x01010101;
+        do {
+            AV_WN32A(ptr,     v32);
+            AV_WN32A(ptr + 4, v32);
+            ptr += stride;
+        } while (--h);
+#endif
+        break;
+    }
+    }
+}
+
+static void decode_mode(AVCodecContext *ctx)
+{
+    static const uint8_t left_ctx[N_BS_SIZES] = {
+        0x0, 0x8, 0x0, 0x8, 0xc, 0x8, 0xc, 0xe, 0xc, 0xe, 0xf, 0xe, 0xf
+    };
+    static const uint8_t above_ctx[N_BS_SIZES] = {
+        0x0, 0x0, 0x8, 0x8, 0x8, 0xc, 0xc, 0xc, 0xe, 0xe, 0xe, 0xf, 0xf
+    };
+    static const uint8_t max_tx_for_bl_bp[N_BS_SIZES] = {
+        TX_32X32, TX_32X32, TX_32X32, TX_32X32, TX_16X16, TX_16X16,
+        TX_16X16, TX_8X8, TX_8X8, TX_8X8, TX_4X4, TX_4X4, TX_4X4
+    };
+    VP9Context *s = ctx->priv_data;
+    VP9Block *b = s->b;
+    int row = s->row, col = s->col, row7 = s->row7;
+    enum TxfmMode max_tx = max_tx_for_bl_bp[b->bs];
+    int bw4 = bwh_tab[1][b->bs][0], w4 = FFMIN(s->cols - col, bw4);
+    int bh4 = bwh_tab[1][b->bs][1], h4 = FFMIN(s->rows - row, bh4), y;
+    int have_a = row > 0, have_l = col > s->tiling.tile_col_start;
+    int vref, filter_id;
+
+    if (!s->segmentation.enabled) {
+        b->seg_id = 0;
+    } else if (s->keyframe || s->intraonly) {
+        b->seg_id = vp8_rac_get_tree(&s->c, vp9_segmentation_tree, s->prob.seg);
+    } else if (!s->segmentation.update_map ||
+               (s->segmentation.temporal &&
+                vp56_rac_get_prob_branchy(&s->c,
+                    s->prob.segpred[s->above_segpred_ctx[col] +
+                                    s->left_segpred_ctx[row7]]))) {
+        if (!s->errorres && !s->segmentation.ignore_refmap) {
+            int pred = 8, x;
+            uint8_t *refsegmap = s->frames[REF_FRAME_SEGMAP].segmentation_map;
+
+            if (!s->frames[REF_FRAME_SEGMAP].uses_2pass)
+                ff_thread_await_progress(&s->frames[REF_FRAME_SEGMAP].tf, row >> 3, 0);
+            for (y = 0; y < h4; y++) {
+                int idx_base = (y + row) * 8 * s->sb_cols + col;
+                for (x = 0; x < w4; x++)
+                    pred = FFMIN(pred, refsegmap[idx_base + x]);
+            }
+            av_assert1(pred < 8);
+            b->seg_id = pred;
+        } else {
+            b->seg_id = 0;
+        }
+
+        memset(&s->above_segpred_ctx[col], 1, w4);
+        memset(&s->left_segpred_ctx[row7], 1, h4);
+    } else {
+        b->seg_id = vp8_rac_get_tree(&s->c, vp9_segmentation_tree,
+                                     s->prob.seg);
+
+        memset(&s->above_segpred_ctx[col], 0, w4);
+        memset(&s->left_segpred_ctx[row7], 0, h4);
+    }
+    if (s->segmentation.enabled &&
+        (s->segmentation.update_map || s->keyframe || s->intraonly)) {
+        setctx_2d(&s->frames[CUR_FRAME].segmentation_map[row * 8 * s->sb_cols + col],
+                  bw4, bh4, 8 * s->sb_cols, b->seg_id);
+    }
+
+    b->skip = s->segmentation.enabled &&
+        s->segmentation.feat[b->seg_id].skip_enabled;
+    if (!b->skip) {
+        int c = s->left_skip_ctx[row7] + s->above_skip_ctx[col];
+        b->skip = vp56_rac_get_prob(&s->c, s->prob.p.skip[c]);
+        s->counts.skip[c][b->skip]++;
+    }
+
+    if (s->keyframe || s->intraonly) {
+        b->intra = 1;
+    } else if (s->segmentation.feat[b->seg_id].ref_enabled) {
+        b->intra = !s->segmentation.feat[b->seg_id].ref_val;
+    } else {
+        int c, bit;
+
+        if (have_a && have_l) {
+            c = s->above_intra_ctx[col] + s->left_intra_ctx[row7];
+            c += (c == 2);
+        } else {
+            c = have_a ? 2 * s->above_intra_ctx[col] :
+                have_l ? 2 * s->left_intra_ctx[row7] : 0;
+        }
+        bit = vp56_rac_get_prob(&s->c, s->prob.p.intra[c]);
+        s->counts.intra[c][bit]++;
+        b->intra = !bit;
+    }
+
+    if ((b->intra || !b->skip) && s->txfmmode == TX_SWITCHABLE) {
+        int c;
+        if (have_a) {
+            if (have_l) {
+                c = (s->above_skip_ctx[col] ? max_tx :
+                     s->above_txfm_ctx[col]) +
+                    (s->left_skip_ctx[row7] ? max_tx :
+                     s->left_txfm_ctx[row7]) > max_tx;
+            } else {
+                c = s->above_skip_ctx[col] ? 1 :
+                    (s->above_txfm_ctx[col] * 2 > max_tx);
+            }
+        } else if (have_l) {
+            c = s->left_skip_ctx[row7] ? 1 :
+                (s->left_txfm_ctx[row7] * 2 > max_tx);
+        } else {
+            c = 1;
+        }
+        switch (max_tx) {
+        case TX_32X32:
+            b->tx = vp56_rac_get_prob(&s->c, s->prob.p.tx32p[c][0]);
+            if (b->tx) {
+                b->tx += vp56_rac_get_prob(&s->c, s->prob.p.tx32p[c][1]);
+                if (b->tx == 2)
+                    b->tx += vp56_rac_get_prob(&s->c, s->prob.p.tx32p[c][2]);
+            }
+            s->counts.tx32p[c][b->tx]++;
+            break;
+        case TX_16X16:
+            b->tx = vp56_rac_get_prob(&s->c, s->prob.p.tx16p[c][0]);
+            if (b->tx)
+                b->tx += vp56_rac_get_prob(&s->c, s->prob.p.tx16p[c][1]);
+            s->counts.tx16p[c][b->tx]++;
+            break;
+        case TX_8X8:
+            b->tx = vp56_rac_get_prob(&s->c, s->prob.p.tx8p[c]);
+            s->counts.tx8p[c][b->tx]++;
+            break;
+        case TX_4X4:
+            b->tx = TX_4X4;
+            break;
+        }
+    } else {
+        b->tx = FFMIN(max_tx, s->txfmmode);
+    }
+
+    if (s->keyframe || s->intraonly) {
+        uint8_t *a = &s->above_mode_ctx[col * 2];
+        uint8_t *l = &s->left_mode_ctx[(row7) << 1];
+
+        b->comp = 0;
+        if (b->bs > BS_8x8) {
+            // FIXME the memory storage intermediates here aren't really
+            // necessary, they're just there to make the code slightly
+            // simpler for now
+            b->mode[0] = a[0] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                    vp9_default_kf_ymode_probs[a[0]][l[0]]);
+            if (b->bs != BS_8x4) {
+                b->mode[1] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                 vp9_default_kf_ymode_probs[a[1]][b->mode[0]]);
+                l[0] = a[1] = b->mode[1];
+            } else {
+                l[0] = a[1] = b->mode[1] = b->mode[0];
+            }
+            if (b->bs != BS_4x8) {
+                b->mode[2] = a[0] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                        vp9_default_kf_ymode_probs[a[0]][l[1]]);
+                if (b->bs != BS_8x4) {
+                    b->mode[3] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                  vp9_default_kf_ymode_probs[a[1]][b->mode[2]]);
+                    l[1] = a[1] = b->mode[3];
+                } else {
+                    l[1] = a[1] = b->mode[3] = b->mode[2];
+                }
+            } else {
+                b->mode[2] = b->mode[0];
+                l[1] = a[1] = b->mode[3] = b->mode[1];
+            }
+        } else {
+            b->mode[0] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                          vp9_default_kf_ymode_probs[*a][*l]);
+            b->mode[3] = b->mode[2] = b->mode[1] = b->mode[0];
+            // FIXME this can probably be optimized
+            memset(a, b->mode[0], bwh_tab[0][b->bs][0]);
+            memset(l, b->mode[0], bwh_tab[0][b->bs][1]);
+        }
+        b->uvmode = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                     vp9_default_kf_uvmode_probs[b->mode[3]]);
+    } else if (b->intra) {
+        b->comp = 0;
+        if (b->bs > BS_8x8) {
+            b->mode[0] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                          s->prob.p.y_mode[0]);
+            s->counts.y_mode[0][b->mode[0]]++;
+            if (b->bs != BS_8x4) {
+                b->mode[1] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                              s->prob.p.y_mode[0]);
+                s->counts.y_mode[0][b->mode[1]]++;
+            } else {
+                b->mode[1] = b->mode[0];
+            }
+            if (b->bs != BS_4x8) {
+                b->mode[2] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                              s->prob.p.y_mode[0]);
+                s->counts.y_mode[0][b->mode[2]]++;
+                if (b->bs != BS_8x4) {
+                    b->mode[3] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                                  s->prob.p.y_mode[0]);
+                    s->counts.y_mode[0][b->mode[3]]++;
+                } else {
+                    b->mode[3] = b->mode[2];
+                }
+            } else {
+                b->mode[2] = b->mode[0];
+                b->mode[3] = b->mode[1];
+            }
+        } else {
+            static const uint8_t size_group[10] = {
+                3, 3, 3, 3, 2, 2, 2, 1, 1, 1
+            };
+            int sz = size_group[b->bs];
+
+            b->mode[0] = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                          s->prob.p.y_mode[sz]);
+            b->mode[1] = b->mode[2] = b->mode[3] = b->mode[0];
+            s->counts.y_mode[sz][b->mode[3]]++;
+        }
+        b->uvmode = vp8_rac_get_tree(&s->c, vp9_intramode_tree,
+                                     s->prob.p.uv_mode[b->mode[3]]);
+        s->counts.uv_mode[b->mode[3]][b->uvmode]++;
+    } else {
+        static const uint8_t inter_mode_ctx_lut[14][14] = {
+            { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
+            { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
+            { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
+            { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
+            { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
+            { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
+            { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
+            { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
+            { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
+            { 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 5, 5, 5 },
+            { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 2, 2, 1, 3 },
+            { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 2, 2, 1, 3 },
+            { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 1, 1, 0, 3 },
+            { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 3, 3, 3, 4 },
+        };
+
+        if (s->segmentation.feat[b->seg_id].ref_enabled) {
+            av_assert2(s->segmentation.feat[b->seg_id].ref_val != 0);
+            b->comp = 0;
+            b->ref[0] = s->segmentation.feat[b->seg_id].ref_val - 1;
+        } else {
+            // read comp_pred flag
+            if (s->comppredmode != PRED_SWITCHABLE) {
+                b->comp = s->comppredmode == PRED_COMPREF;
+            } else {
+                int c;
+
+                // FIXME add intra as ref=0xff (or -1) to make these easier?
+                if (have_a) {
+                    if (have_l) {
+                        if (s->above_comp_ctx[col] && s->left_comp_ctx[row7]) {
+                            c = 4;
+                        } else if (s->above_comp_ctx[col]) {
+                            c = 2 + (s->left_intra_ctx[row7] ||
+                                     s->left_ref_ctx[row7] == s->fixcompref);
+                        } else if (s->left_comp_ctx[row7]) {
+                            c = 2 + (s->above_intra_ctx[col] ||
+                                     s->above_ref_ctx[col] == s->fixcompref);
+                        } else {
+                            c = (!s->above_intra_ctx[col] &&
+                                 s->above_ref_ctx[col] == s->fixcompref) ^
+                            (!s->left_intra_ctx[row7] &&
+                             s->left_ref_ctx[row & 7] == s->fixcompref);
+                        }
+                    } else {
+                        c = s->above_comp_ctx[col] ? 3 :
+                        (!s->above_intra_ctx[col] && s->above_ref_ctx[col] == s->fixcompref);
+                    }
+                } else if (have_l) {
+                    c = s->left_comp_ctx[row7] ? 3 :
+                    (!s->left_intra_ctx[row7] && s->left_ref_ctx[row7] == s->fixcompref);
+                } else {
+                    c = 1;
+                }
+                b->comp = vp56_rac_get_prob(&s->c, s->prob.p.comp[c]);
+                s->counts.comp[c][b->comp]++;
+            }
+
+            // read actual references
+            // FIXME probably cache a few variables here to prevent repetitive
+            // memory accesses below
+            if (b->comp) /* two references */ {
+                int fix_idx = s->signbias[s->fixcompref], var_idx = !fix_idx, c, bit;
+
+                b->ref[fix_idx] = s->fixcompref;
+                // FIXME can this codeblob be replaced by some sort of LUT?
+                if (have_a) {
+                    if (have_l) {
+                        if (s->above_intra_ctx[col]) {
+                            if (s->left_intra_ctx[row7]) {
+                                c = 2;
+                            } else {
+                                c = 1 + 2 * (s->left_ref_ctx[row7] != s->varcompref[1]);
+                            }
+                        } else if (s->left_intra_ctx[row7]) {
+                            c = 1 + 2 * (s->above_ref_ctx[col] != s->varcompref[1]);
+                        } else {
+                            int refl = s->left_ref_ctx[row7], refa = s->above_ref_ctx[col];
+
+                            if (refl == refa && refa == s->varcompref[1]) {
+                                c = 0;
+                            } else if (!s->left_comp_ctx[row7] && !s->above_comp_ctx[col]) {
+                                if ((refa == s->fixcompref && refl == s->varcompref[0]) ||
+                                    (refl == s->fixcompref && refa == s->varcompref[0])) {
+                                    c = 4;
+                                } else {
+                                    c = (refa == refl) ? 3 : 1;
+                                }
+                            } else if (!s->left_comp_ctx[row7]) {
+                                if (refa == s->varcompref[1] && refl != s->varcompref[1]) {
+                                    c = 1;
+                                } else {
+                                    c = (refl == s->varcompref[1] &&
+                                         refa != s->varcompref[1]) ? 2 : 4;
+                                }
+                            } else if (!s->above_comp_ctx[col]) {
+                                if (refl == s->varcompref[1] && refa != s->varcompref[1]) {
+                                    c = 1;
+                                } else {
+                                    c = (refa == s->varcompref[1] &&
+                                         refl != s->varcompref[1]) ? 2 : 4;
+                                }
+                            } else {
+                                c = (refl == refa) ? 4 : 2;
+                            }
+                        }
+                    } else {
+                        if (s->above_intra_ctx[col]) {
+                            c = 2;
+                        } else if (s->above_comp_ctx[col]) {
+                            c = 4 * (s->above_ref_ctx[col] != s->varcompref[1]);
+                        } else {
+                            c = 3 * (s->above_ref_ctx[col] != s->varcompref[1]);
+                        }
+                    }
+                } else if (have_l) {
+                    if (s->left_intra_ctx[row7]) {
+                        c = 2;
+                    } else if (s->left_comp_ctx[row7]) {
+                        c = 4 * (s->left_ref_ctx[row7] != s->varcompref[1]);
+                    } else {
+                        c = 3 * (s->left_ref_ctx[row7] != s->varcompref[1]);
+                    }
+                } else {
+                    c = 2;
+                }
+                bit = vp56_rac_get_prob(&s->c, s->prob.p.comp_ref[c]);
+                b->ref[var_idx] = s->varcompref[bit];
+                s->counts.comp_ref[c][bit]++;
+            } else /* single reference */ {
+                int bit, c;
+
+                if (have_a && !s->above_intra_ctx[col]) {
+                    if (have_l && !s->left_intra_ctx[row7]) {
+                        if (s->left_comp_ctx[row7]) {
+                            if (s->above_comp_ctx[col]) {
+                                c = 1 + (!s->fixcompref || !s->left_ref_ctx[row7] ||
+                                         !s->above_ref_ctx[col]);
+                            } else {
+                                c = (3 * !s->above_ref_ctx[col]) +
+                                    (!s->fixcompref || !s->left_ref_ctx[row7]);
+                            }
+                        } else if (s->above_comp_ctx[col]) {
+                            c = (3 * !s->left_ref_ctx[row7]) +
+                                (!s->fixcompref || !s->above_ref_ctx[col]);
+                        } else {
+                            c = 2 * !s->left_ref_ctx[row7] + 2 * !s->above_ref_ctx[col];
+                        }
+                    } else if (s->above_intra_ctx[col]) {
+                        c = 2;
+                    } else if (s->above_comp_ctx[col]) {
+                        c = 1 + (!s->fixcompref || !s->above_ref_ctx[col]);
+                    } else {
+                        c = 4 * (!s->above_ref_ctx[col]);
+                    }
+                } else if (have_l && !s->left_intra_ctx[row7]) {
+                    if (s->left_intra_ctx[row7]) {
+                        c = 2;
+                    } else if (s->left_comp_ctx[row7]) {
+                        c = 1 + (!s->fixcompref || !s->left_ref_ctx[row7]);
+                    } else {
+                        c = 4 * (!s->left_ref_ctx[row7]);
+                    }
+                } else {
+                    c = 2;
+                }
+                bit = vp56_rac_get_prob(&s->c, s->prob.p.single_ref[c][0]);
+                s->counts.single_ref[c][0][bit]++;
+                if (!bit) {
+                    b->ref[0] = 0;
+                } else {
+                    // FIXME can this codeblob be replaced by some sort of LUT?
+                    if (have_a) {
+                        if (have_l) {
+                            if (s->left_intra_ctx[row7]) {
+                                if (s->above_intra_ctx[col]) {
+                                    c = 2;
+                                } else if (s->above_comp_ctx[col]) {
+                                    c = 1 + 2 * (s->fixcompref == 1 ||
+                                                 s->above_ref_ctx[col] == 1);
+                                } else if (!s->above_ref_ctx[col]) {
+                                    c = 3;
+                                } else {
+                                    c = 4 * (s->above_ref_ctx[col] == 1);
+                                }
+                            } else if (s->above_intra_ctx[col]) {
+                                if (s->left_intra_ctx[row7]) {
+                                    c = 2;
+                                } else if (s->left_comp_ctx[row7]) {
+                                    c = 1 + 2 * (s->fixcompref == 1 ||
+                                                 s->left_ref_ctx[row7] == 1);
+                                } else if (!s->left_ref_ctx[row7]) {
+                                    c = 3;
+                                } else {
+                                    c = 4 * (s->left_ref_ctx[row7] == 1);
+                                }
+                            } else if (s->above_comp_ctx[col]) {
+                                if (s->left_comp_ctx[row7]) {
+                                    if (s->left_ref_ctx[row7] == s->above_ref_ctx[col]) {
+                                        c = 3 * (s->fixcompref == 1 ||
+                                                 s->left_ref_ctx[row7] == 1);
+                                    } else {
+                                        c = 2;
+                                    }
+                                } else if (!s->left_ref_ctx[row7]) {
+                                    c = 1 + 2 * (s->fixcompref == 1 ||
+                                                 s->above_ref_ctx[col] == 1);
+                                } else {
+                                    c = 3 * (s->left_ref_ctx[row7] == 1) +
+                                    (s->fixcompref == 1 || s->above_ref_ctx[col] == 1);
+                                }
+                            } else if (s->left_comp_ctx[row7]) {
+                                if (!s->above_ref_ctx[col]) {
+                                    c = 1 + 2 * (s->fixcompref == 1 ||
+                                                 s->left_ref_ctx[row7] == 1);
+                                } else {
+                                    c = 3 * (s->above_ref_ctx[col] == 1) +
+                                    (s->fixcompref == 1 || s->left_ref_ctx[row7] == 1);
+                                }
+                            } else if (!s->above_ref_ctx[col]) {
+                                if (!s->left_ref_ctx[row7]) {
+                                    c = 3;
+                                } else {
+                                    c = 4 * (s->left_ref_ctx[row7] == 1);
+                                }
+                            } else if (!s->left_ref_ctx[row7]) {
+                                c = 4 * (s->above_ref_ctx[col] == 1);
+                            } else {
+                                c = 2 * (s->left_ref_ctx[row7] == 1) +
+                                2 * (s->above_ref_ctx[col] == 1);
+                            }
+                        } else {
+                            if (s->above_intra_ctx[col] ||
+                                (!s->above_comp_ctx[col] && !s->above_ref_ctx[col])) {
+                                c = 2;
+                            } else if (s->above_comp_ctx[col]) {
+                                c = 3 * (s->fixcompref == 1 || s->above_ref_ctx[col] == 1);
+                            } else {
+                                c = 4 * (s->above_ref_ctx[col] == 1);
+                            }
+                        }
+                    } else if (have_l) {
+                        if (s->left_intra_ctx[row7] ||
+                            (!s->left_comp_ctx[row7] && !s->left_ref_ctx[row7])) {
+                            c = 2;
+                        } else if (s->left_comp_ctx[row7]) {
+                            c = 3 * (s->fixcompref == 1 || s->left_ref_ctx[row7] == 1);
+                        } else {
+                            c = 4 * (s->left_ref_ctx[row7] == 1);
+                        }
+                    } else {
+                        c = 2;
+                    }
+                    bit = vp56_rac_get_prob(&s->c, s->prob.p.single_ref[c][1]);
+                    s->counts.single_ref[c][1][bit]++;
+                    b->ref[0] = 1 + bit;
+                }
+            }
+        }
+
+        if (b->bs <= BS_8x8) {
+            if (s->segmentation.feat[b->seg_id].skip_enabled) {
+                b->mode[0] = b->mode[1] = b->mode[2] = b->mode[3] = ZEROMV;
+            } else {
+                static const uint8_t off[10] = {
+                    3, 0, 0, 1, 0, 0, 0, 0, 0, 0
+                };
+
+                // FIXME this needs to use the LUT tables from find_ref_mvs
+                // because not all are -1,0/0,-1
+                int c = inter_mode_ctx_lut[s->above_mode_ctx[col + off[b->bs]]]
+                                          [s->left_mode_ctx[row7 + off[b->bs]]];
+
+                b->mode[0] = vp8_rac_get_tree(&s->c, vp9_inter_mode_tree,
+                                              s->prob.p.mv_mode[c]);
+                b->mode[1] = b->mode[2] = b->mode[3] = b->mode[0];
+                s->counts.mv_mode[c][b->mode[0] - 10]++;
+            }
+        }
+
+        if (s->filtermode == FILTER_SWITCHABLE) {
+            int c;
+
+            if (have_a && s->above_mode_ctx[col] >= NEARESTMV) {
+                if (have_l && s->left_mode_ctx[row7] >= NEARESTMV) {
+                    c = s->above_filter_ctx[col] == s->left_filter_ctx[row7] ?
+                        s->left_filter_ctx[row7] : 3;
+                } else {
+                    c = s->above_filter_ctx[col];
+                }
+            } else if (have_l && s->left_mode_ctx[row7] >= NEARESTMV) {
+                c = s->left_filter_ctx[row7];
+            } else {
+                c = 3;
+            }
+
+            filter_id = vp8_rac_get_tree(&s->c, vp9_filter_tree,
+                                         s->prob.p.filter[c]);
+            s->counts.filter[c][filter_id]++;
+            b->filter = vp9_filter_lut[filter_id];
+        } else {
+            b->filter = s->filtermode;
+        }
+
+        if (b->bs > BS_8x8) {
+            int c = inter_mode_ctx_lut[s->above_mode_ctx[col]][s->left_mode_ctx[row7]];
+
+            b->mode[0] = vp8_rac_get_tree(&s->c, vp9_inter_mode_tree,
+                                          s->prob.p.mv_mode[c]);
+            s->counts.mv_mode[c][b->mode[0] - 10]++;
+            fill_mv(s, b->mv[0], b->mode[0], 0);
+
+            if (b->bs != BS_8x4) {
+                b->mode[1] = vp8_rac_get_tree(&s->c, vp9_inter_mode_tree,
+                                              s->prob.p.mv_mode[c]);
+                s->counts.mv_mode[c][b->mode[1] - 10]++;
+                fill_mv(s, b->mv[1], b->mode[1], 1);
+            } else {
+                b->mode[1] = b->mode[0];
+                AV_COPY32(&b->mv[1][0], &b->mv[0][0]);
+                AV_COPY32(&b->mv[1][1], &b->mv[0][1]);
+            }
+
+            if (b->bs != BS_4x8) {
+                b->mode[2] = vp8_rac_get_tree(&s->c, vp9_inter_mode_tree,
+                                              s->prob.p.mv_mode[c]);
+                s->counts.mv_mode[c][b->mode[2] - 10]++;
+                fill_mv(s, b->mv[2], b->mode[2], 2);
+
+                if (b->bs != BS_8x4) {
+                    b->mode[3] = vp8_rac_get_tree(&s->c, vp9_inter_mode_tree,
+                                                  s->prob.p.mv_mode[c]);
+                    s->counts.mv_mode[c][b->mode[3] - 10]++;
+                    fill_mv(s, b->mv[3], b->mode[3], 3);
+                } else {
+                    b->mode[3] = b->mode[2];
+                    AV_COPY32(&b->mv[3][0], &b->mv[2][0]);
+                    AV_COPY32(&b->mv[3][1], &b->mv[2][1]);
+                }
+            } else {
+                b->mode[2] = b->mode[0];
+                AV_COPY32(&b->mv[2][0], &b->mv[0][0]);
+                AV_COPY32(&b->mv[2][1], &b->mv[0][1]);
+                b->mode[3] = b->mode[1];
+                AV_COPY32(&b->mv[3][0], &b->mv[1][0]);
+                AV_COPY32(&b->mv[3][1], &b->mv[1][1]);
+            }
+        } else {
+            fill_mv(s, b->mv[0], b->mode[0], -1);
+            AV_COPY32(&b->mv[1][0], &b->mv[0][0]);
+            AV_COPY32(&b->mv[2][0], &b->mv[0][0]);
+            AV_COPY32(&b->mv[3][0], &b->mv[0][0]);
+            AV_COPY32(&b->mv[1][1], &b->mv[0][1]);
+            AV_COPY32(&b->mv[2][1], &b->mv[0][1]);
+            AV_COPY32(&b->mv[3][1], &b->mv[0][1]);
+        }
+
+        vref = b->ref[b->comp ? s->signbias[s->varcompref[0]] : 0];
+    }
+
+#if HAVE_FAST_64BIT
+#define SPLAT_CTX(var, val, n) \
+    switch (n) { \
+    case 1:  var = val;                                    break; \
+    case 2:  AV_WN16A(&var, val *             0x0101);     break; \
+    case 4:  AV_WN32A(&var, val *         0x01010101);     break; \
+    case 8:  AV_WN64A(&var, val * 0x0101010101010101ULL);  break; \
+    case 16: { \
+        uint64_t v64 = val * 0x0101010101010101ULL; \
+        AV_WN64A(              &var,     v64); \
+        AV_WN64A(&((uint8_t *) &var)[8], v64); \
+        break; \
+    } \
+    }
+#else
+#define SPLAT_CTX(var, val, n) \
+    switch (n) { \
+    case 1:  var = val;                         break; \
+    case 2:  AV_WN16A(&var, val *     0x0101);  break; \
+    case 4:  AV_WN32A(&var, val * 0x01010101);  break; \
+    case 8: { \
+        uint32_t v32 = val * 0x01010101; \
+        AV_WN32A(              &var,     v32); \
+        AV_WN32A(&((uint8_t *) &var)[4], v32); \
+        break; \
+    } \
+    case 16: { \
+        uint32_t v32 = val * 0x01010101; \
+        AV_WN32A(              &var,      v32); \
+        AV_WN32A(&((uint8_t *) &var)[4],  v32); \
+        AV_WN32A(&((uint8_t *) &var)[8],  v32); \
+        AV_WN32A(&((uint8_t *) &var)[12], v32); \
+        break; \
+    } \
+    }
+#endif
+
+    switch (bwh_tab[1][b->bs][0]) {
+#define SET_CTXS(dir, off, n) \
+    do { \
+        SPLAT_CTX(s->dir##_skip_ctx[off],      b->skip,          n); \
+        SPLAT_CTX(s->dir##_txfm_ctx[off],      b->tx,            n); \
+        SPLAT_CTX(s->dir##_partition_ctx[off], dir##_ctx[b->bs], n); \
+        if (!s->keyframe && !s->intraonly) { \
+            SPLAT_CTX(s->dir##_intra_ctx[off], b->intra,   n); \
+            SPLAT_CTX(s->dir##_comp_ctx[off],  b->comp,    n); \
+            SPLAT_CTX(s->dir##_mode_ctx[off],  b->mode[3], n); \
+            if (!b->intra) { \
+                SPLAT_CTX(s->dir##_ref_ctx[off], vref, n); \
+                if (s->filtermode == FILTER_SWITCHABLE) { \
+                    SPLAT_CTX(s->dir##_filter_ctx[off], filter_id, n); \
+                } \
+            } \
+        } \
+    } while (0)
+    case 1: SET_CTXS(above, col, 1); break;
+    case 2: SET_CTXS(above, col, 2); break;
+    case 4: SET_CTXS(above, col, 4); break;
+    case 8: SET_CTXS(above, col, 8); break;
+    }
+    switch (bwh_tab[1][b->bs][1]) {
+    case 1: SET_CTXS(left, row7, 1); break;
+    case 2: SET_CTXS(left, row7, 2); break;
+    case 4: SET_CTXS(left, row7, 4); break;
+    case 8: SET_CTXS(left, row7, 8); break;
+    }
+#undef SPLAT_CTX
+#undef SET_CTXS
+
+    if (!s->keyframe && !s->intraonly) {
+        if (b->bs > BS_8x8) {
+            int mv0 = AV_RN32A(&b->mv[3][0]), mv1 = AV_RN32A(&b->mv[3][1]);
+
+            AV_COPY32(&s->left_mv_ctx[row7 * 2 + 0][0], &b->mv[1][0]);
+            AV_COPY32(&s->left_mv_ctx[row7 * 2 + 0][1], &b->mv[1][1]);
+            AV_WN32A(&s->left_mv_ctx[row7 * 2 + 1][0], mv0);
+            AV_WN32A(&s->left_mv_ctx[row7 * 2 + 1][1], mv1);
+            AV_COPY32(&s->above_mv_ctx[col * 2 + 0][0], &b->mv[2][0]);
+            AV_COPY32(&s->above_mv_ctx[col * 2 + 0][1], &b->mv[2][1]);
+            AV_WN32A(&s->above_mv_ctx[col * 2 + 1][0], mv0);
+            AV_WN32A(&s->above_mv_ctx[col * 2 + 1][1], mv1);
+        } else {
+            int n, mv0 = AV_RN32A(&b->mv[3][0]), mv1 = AV_RN32A(&b->mv[3][1]);
+
+            for (n = 0; n < w4 * 2; n++) {
+                AV_WN32A(&s->above_mv_ctx[col * 2 + n][0], mv0);
+                AV_WN32A(&s->above_mv_ctx[col * 2 + n][1], mv1);
+            }
+            for (n = 0; n < h4 * 2; n++) {
+                AV_WN32A(&s->left_mv_ctx[row7 * 2 + n][0], mv0);
+                AV_WN32A(&s->left_mv_ctx[row7 * 2 + n][1], mv1);
+            }
+        }
+    }
+
+    // FIXME kinda ugly
+    for (y = 0; y < h4; y++) {
+        int x, o = (row + y) * s->sb_cols * 8 + col;
+        struct VP9mvrefPair *mv = &s->frames[CUR_FRAME].mv[o];
+
+        if (b->intra) {
+            for (x = 0; x < w4; x++) {
+                mv[x].ref[0] =
+                mv[x].ref[1] = -1;
+            }
+        } else if (b->comp) {
+            for (x = 0; x < w4; x++) {
+                mv[x].ref[0] = b->ref[0];
+                mv[x].ref[1] = b->ref[1];
+                AV_COPY32(&mv[x].mv[0], &b->mv[3][0]);
+                AV_COPY32(&mv[x].mv[1], &b->mv[3][1]);
+            }
+        } else {
+            for (x = 0; x < w4; x++) {
+                mv[x].ref[0] = b->ref[0];
+                mv[x].ref[1] = -1;
+                AV_COPY32(&mv[x].mv[0], &b->mv[3][0]);
+            }
+        }
+    }
+}
+
+// FIXME merge cnt/eob arguments?
+static av_always_inline int
+decode_coeffs_b_generic(VP56RangeCoder *c, int16_t *coef, int n_coeffs,
+                        int is_tx32x32, int is8bitsperpixel, int bpp, unsigned (*cnt)[6][3],
+                        unsigned (*eob)[6][2], uint8_t (*p)[6][11],
+                        int nnz, const int16_t *scan, const int16_t (*nb)[2],
+                        const int16_t *band_counts, const int16_t *qmul)
+{
+    int i = 0, band = 0, band_left = band_counts[band];
+    uint8_t *tp = p[0][nnz];
+    uint8_t cache[1024];
+
+    do {
+        int val, rc;
+
+        val = vp56_rac_get_prob_branchy(c, tp[0]); // eob
+        eob[band][nnz][val]++;
+        if (!val)
+            break;
+
+    skip_eob:
+        if (!vp56_rac_get_prob_branchy(c, tp[1])) { // zero
+            cnt[band][nnz][0]++;
+            if (!--band_left)
+                band_left = band_counts[++band];
+            cache[scan[i]] = 0;
+            nnz = (1 + cache[nb[i][0]] + cache[nb[i][1]]) >> 1;
+            tp = p[band][nnz];
+            if (++i == n_coeffs)
+                break; //invalid input; blocks should end with EOB
+            goto skip_eob;
+        }
+
+        rc = scan[i];
+        if (!vp56_rac_get_prob_branchy(c, tp[2])) { // one
+            cnt[band][nnz][1]++;
+            val = 1;
+            cache[rc] = 1;
+        } else {
+            // fill in p[3-10] (model fill) - only once per frame for each pos
+            if (!tp[3])
+                memcpy(&tp[3], vp9_model_pareto8[tp[2]], 8);
+
+            cnt[band][nnz][2]++;
+            if (!vp56_rac_get_prob_branchy(c, tp[3])) { // 2, 3, 4
+                if (!vp56_rac_get_prob_branchy(c, tp[4])) {
+                    cache[rc] = val = 2;
+                } else {
+                    val = 3 + vp56_rac_get_prob(c, tp[5]);
+                    cache[rc] = 3;
+                }
+            } else if (!vp56_rac_get_prob_branchy(c, tp[6])) { // cat1/2
+                cache[rc] = 4;
+                if (!vp56_rac_get_prob_branchy(c, tp[7])) {
+                    val = 5 + vp56_rac_get_prob(c, 159);
+                } else {
+                    val  = 7 + (vp56_rac_get_prob(c, 165) << 1);
+                    val +=      vp56_rac_get_prob(c, 145);
+                }
+            } else { // cat 3-6
+                cache[rc] = 5;
+                if (!vp56_rac_get_prob_branchy(c, tp[8])) {
+                    if (!vp56_rac_get_prob_branchy(c, tp[9])) {
+                        val  = 11 + (vp56_rac_get_prob(c, 173) << 2);
+                        val +=      (vp56_rac_get_prob(c, 148) << 1);
+                        val +=       vp56_rac_get_prob(c, 140);
+                    } else {
+                        val  = 19 + (vp56_rac_get_prob(c, 176) << 3);
+                        val +=      (vp56_rac_get_prob(c, 155) << 2);
+                        val +=      (vp56_rac_get_prob(c, 140) << 1);
+                        val +=       vp56_rac_get_prob(c, 135);
+                    }
+                } else if (!vp56_rac_get_prob_branchy(c, tp[10])) {
+                    val  = 35 + (vp56_rac_get_prob(c, 180) << 4);
+                    val +=      (vp56_rac_get_prob(c, 157) << 3);
+                    val +=      (vp56_rac_get_prob(c, 141) << 2);
+                    val +=      (vp56_rac_get_prob(c, 134) << 1);
+                    val +=       vp56_rac_get_prob(c, 130);
+                } else {
+                    val = 67;
+                    if (!is8bitsperpixel) {
+                        if (bpp == 12) {
+                            val += vp56_rac_get_prob(c, 255) << 17;
+                            val += vp56_rac_get_prob(c, 255) << 16;
+                        }
+                        val +=  (vp56_rac_get_prob(c, 255) << 15);
+                        val +=  (vp56_rac_get_prob(c, 255) << 14);
+                    }
+                    val +=      (vp56_rac_get_prob(c, 254) << 13);
+                    val +=      (vp56_rac_get_prob(c, 254) << 12);
+                    val +=      (vp56_rac_get_prob(c, 254) << 11);
+                    val +=      (vp56_rac_get_prob(c, 252) << 10);
+                    val +=      (vp56_rac_get_prob(c, 249) << 9);
+                    val +=      (vp56_rac_get_prob(c, 243) << 8);
+                    val +=      (vp56_rac_get_prob(c, 230) << 7);
+                    val +=      (vp56_rac_get_prob(c, 196) << 6);
+                    val +=      (vp56_rac_get_prob(c, 177) << 5);
+                    val +=      (vp56_rac_get_prob(c, 153) << 4);
+                    val +=      (vp56_rac_get_prob(c, 140) << 3);
+                    val +=      (vp56_rac_get_prob(c, 133) << 2);
+                    val +=      (vp56_rac_get_prob(c, 130) << 1);
+                    val +=       vp56_rac_get_prob(c, 129);
+                }
+            }
+        }
+#define STORE_COEF(c, i, v) do { \
+    if (is8bitsperpixel) { \
+        c[i] = v; \
+    } else { \
+        AV_WN32A(&c[i * 2], v); \
+    } \
+} while (0)
+        if (!--band_left)
+            band_left = band_counts[++band];
+        if (is_tx32x32)
+            STORE_COEF(coef, rc, ((vp8_rac_get(c) ? -val : val) * qmul[!!i]) / 2);
+        else
+            STORE_COEF(coef, rc, (vp8_rac_get(c) ? -val : val) * qmul[!!i]);
+        nnz = (1 + cache[nb[i][0]] + cache[nb[i][1]]) >> 1;
+        tp = p[band][nnz];
+    } while (++i < n_coeffs);
+
+    return i;
+}
+
+static int decode_coeffs_b_8bpp(VP9Context *s, int16_t *coef, int n_coeffs,
+                                unsigned (*cnt)[6][3], unsigned (*eob)[6][2],
+                                uint8_t (*p)[6][11], int nnz, const int16_t *scan,
+                                const int16_t (*nb)[2], const int16_t *band_counts,
+                                const int16_t *qmul)
+{
+    return decode_coeffs_b_generic(&s->c, coef, n_coeffs, 0, 1, 8, cnt, eob, p,
+                                   nnz, scan, nb, band_counts, qmul);
+}
+
+static int decode_coeffs_b32_8bpp(VP9Context *s, int16_t *coef, int n_coeffs,
+                                  unsigned (*cnt)[6][3], unsigned (*eob)[6][2],
+                                  uint8_t (*p)[6][11], int nnz, const int16_t *scan,
+                                  const int16_t (*nb)[2], const int16_t *band_counts,
+                                  const int16_t *qmul)
+{
+    return decode_coeffs_b_generic(&s->c, coef, n_coeffs, 1, 1, 8, cnt, eob, p,
+                                   nnz, scan, nb, band_counts, qmul);
+}
+
+static int decode_coeffs_b_16bpp(VP9Context *s, int16_t *coef, int n_coeffs,
+                                 unsigned (*cnt)[6][3], unsigned (*eob)[6][2],
+                                 uint8_t (*p)[6][11], int nnz, const int16_t *scan,
+                                 const int16_t (*nb)[2], const int16_t *band_counts,
+                                 const int16_t *qmul)
+{
+    return decode_coeffs_b_generic(&s->c, coef, n_coeffs, 0, 0, s->bpp, cnt, eob, p,
+                                   nnz, scan, nb, band_counts, qmul);
+}
+
+static int decode_coeffs_b32_16bpp(VP9Context *s, int16_t *coef, int n_coeffs,
+                                   unsigned (*cnt)[6][3], unsigned (*eob)[6][2],
+                                   uint8_t (*p)[6][11], int nnz, const int16_t *scan,
+                                   const int16_t (*nb)[2], const int16_t *band_counts,
+                                   const int16_t *qmul)
+{
+    return decode_coeffs_b_generic(&s->c, coef, n_coeffs, 1, 0, s->bpp, cnt, eob, p,
+                                   nnz, scan, nb, band_counts, qmul);
+}
+
+static av_always_inline int decode_coeffs(AVCodecContext *ctx, int is8bitsperpixel)
+{
+    VP9Context *s = ctx->priv_data;
+    VP9Block *b = s->b;
+    int row = s->row, col = s->col;
+    uint8_t (*p)[6][11] = s->prob.coef[b->tx][0 /* y */][!b->intra];
+    unsigned (*c)[6][3] = s->counts.coef[b->tx][0 /* y */][!b->intra];
+    unsigned (*e)[6][2] = s->counts.eob[b->tx][0 /* y */][!b->intra];
+    int w4 = bwh_tab[1][b->bs][0] << 1, h4 = bwh_tab[1][b->bs][1] << 1;
+    int end_x = FFMIN(2 * (s->cols - col), w4);
+    int end_y = FFMIN(2 * (s->rows - row), h4);
+    int n, pl, x, y, res;
+    int16_t (*qmul)[2] = s->segmentation.feat[b->seg_id].qmul;
+    int tx = 4 * s->lossless + b->tx;
+    const int16_t * const *yscans = vp9_scans[tx];
+    const int16_t (* const *ynbs)[2] = vp9_scans_nb[tx];
+    const int16_t *uvscan = vp9_scans[b->uvtx][DCT_DCT];
+    const int16_t (*uvnb)[2] = vp9_scans_nb[b->uvtx][DCT_DCT];
+    uint8_t *a = &s->above_y_nnz_ctx[col * 2];
+    uint8_t *l = &s->left_y_nnz_ctx[(row & 7) << 1];
+    static const int16_t band_counts[4][8] = {
+        { 1, 2, 3, 4,  3,   16 - 13 },
+        { 1, 2, 3, 4, 11,   64 - 21 },
+        { 1, 2, 3, 4, 11,  256 - 21 },
+        { 1, 2, 3, 4, 11, 1024 - 21 },
+    };
+    const int16_t *y_band_counts = band_counts[b->tx];
+    const int16_t *uv_band_counts = band_counts[b->uvtx];
+    int bytesperpixel = is8bitsperpixel ? 1 : 2;
+    int total_coeff = 0;
+
+#define MERGE(la, end, step, rd) \
+    for (n = 0; n < end; n += step) \
+        la[n] = !!rd(&la[n])
+#define MERGE_CTX(step, rd) \
+    do { \
+        MERGE(l, end_y, step, rd); \
+        MERGE(a, end_x, step, rd); \
+    } while (0)
+
+#define DECODE_Y_COEF_LOOP(step, mode_index, v) \
+    for (n = 0, y = 0; y < end_y; y += step) { \
+        for (x = 0; x < end_x; x += step, n += step * step) { \
+            enum TxfmType txtp = vp9_intra_txfm_type[b->mode[mode_index]]; \
+            res = (is8bitsperpixel ? decode_coeffs_b##v##_8bpp : decode_coeffs_b##v##_16bpp) \
+                                    (s, s->block + 16 * n * bytesperpixel, 16 * step * step, \
+                                     c, e, p, a[x] + l[y], yscans[txtp], \
+                                     ynbs[txtp], y_band_counts, qmul[0]); \
+            a[x] = l[y] = !!res; \
+            total_coeff |= !!res; \
+            if (step >= 4) { \
+                AV_WN16A(&s->eob[n], res); \
+            } else { \
+                s->eob[n] = res; \
+            } \
+        } \
+    }
+
+#define SPLAT(la, end, step, cond) \
+    if (step == 2) { \
+        for (n = 1; n < end; n += step) \
+            la[n] = la[n - 1]; \
+    } else if (step == 4) { \
+        if (cond) { \
+            for (n = 0; n < end; n += step) \
+                AV_WN32A(&la[n], la[n] * 0x01010101); \
+        } else { \
+            for (n = 0; n < end; n += step) \
+                memset(&la[n + 1], la[n], FFMIN(end - n - 1, 3)); \
+        } \
+    } else /* step == 8 */ { \
+        if (cond) { \
+            if (HAVE_FAST_64BIT) { \
+                for (n = 0; n < end; n += step) \
+                    AV_WN64A(&la[n], la[n] * 0x0101010101010101ULL); \
+            } else { \
+                for (n = 0; n < end; n += step) { \
+                    uint32_t v32 = la[n] * 0x01010101; \
+                    AV_WN32A(&la[n],     v32); \
+                    AV_WN32A(&la[n + 4], v32); \
+                } \
+            } \
+        } else { \
+            for (n = 0; n < end; n += step) \
+                memset(&la[n + 1], la[n], FFMIN(end - n - 1, 7)); \
+        } \
+    }
+#define SPLAT_CTX(step) \
+    do { \
+        SPLAT(a, end_x, step, end_x == w4); \
+        SPLAT(l, end_y, step, end_y == h4); \
+    } while (0)
+
+    /* y tokens */
+    switch (b->tx) {
+    case TX_4X4:
+        DECODE_Y_COEF_LOOP(1, b->bs > BS_8x8 ? n : 0,);
+        break;
+    case TX_8X8:
+        MERGE_CTX(2, AV_RN16A);
+        DECODE_Y_COEF_LOOP(2, 0,);
+        SPLAT_CTX(2);
+        break;
+    case TX_16X16:
+        MERGE_CTX(4, AV_RN32A);
+        DECODE_Y_COEF_LOOP(4, 0,);
+        SPLAT_CTX(4);
+        break;
+    case TX_32X32:
+        MERGE_CTX(8, AV_RN64A);
+        DECODE_Y_COEF_LOOP(8, 0, 32);
+        SPLAT_CTX(8);
+        break;
+    }
+
+#define DECODE_UV_COEF_LOOP(step, v) \
+    for (n = 0, y = 0; y < end_y; y += step) { \
+        for (x = 0; x < end_x; x += step, n += step * step) { \
+            res = (is8bitsperpixel ? decode_coeffs_b##v##_8bpp : decode_coeffs_b##v##_16bpp) \
+                                    (s, s->uvblock[pl] + 16 * n * bytesperpixel, \
+                                     16 * step * step, c, e, p, a[x] + l[y], \
+                                     uvscan, uvnb, uv_band_counts, qmul[1]); \
+            a[x] = l[y] = !!res; \
+            total_coeff |= !!res; \
+            if (step >= 4) { \
+                AV_WN16A(&s->uveob[pl][n], res); \
+            } else { \
+                s->uveob[pl][n] = res; \
+            } \
+        } \
+    }
+
+    p = s->prob.coef[b->uvtx][1 /* uv */][!b->intra];
+    c = s->counts.coef[b->uvtx][1 /* uv */][!b->intra];
+    e = s->counts.eob[b->uvtx][1 /* uv */][!b->intra];
+    w4 >>= s->ss_h;
+    end_x >>= s->ss_h;
+    h4 >>= s->ss_v;
+    end_y >>= s->ss_v;
+    for (pl = 0; pl < 2; pl++) {
+        a = &s->above_uv_nnz_ctx[pl][col << !s->ss_h];
+        l = &s->left_uv_nnz_ctx[pl][(row & 7) << !s->ss_v];
+        switch (b->uvtx) {
+        case TX_4X4:
+            DECODE_UV_COEF_LOOP(1,);
+            break;
+        case TX_8X8:
+            MERGE_CTX(2, AV_RN16A);
+            DECODE_UV_COEF_LOOP(2,);
+            SPLAT_CTX(2);
+            break;
+        case TX_16X16:
+            MERGE_CTX(4, AV_RN32A);
+            DECODE_UV_COEF_LOOP(4,);
+            SPLAT_CTX(4);
+            break;
+        case TX_32X32:
+            MERGE_CTX(8, AV_RN64A);
+            DECODE_UV_COEF_LOOP(8, 32);
+            SPLAT_CTX(8);
+            break;
+        }
+    }
+
+    return total_coeff;
+}
+
+static int decode_coeffs_8bpp(AVCodecContext *ctx)
+{
+    return decode_coeffs(ctx, 1);
+}
+
+static int decode_coeffs_16bpp(AVCodecContext *ctx)
+{
+    return decode_coeffs(ctx, 0);
+}
+
+static av_always_inline int check_intra_mode(VP9Context *s, int mode, uint8_t **a,
+                                             uint8_t *dst_edge, ptrdiff_t stride_edge,
+                                             uint8_t *dst_inner, ptrdiff_t stride_inner,
+                                             uint8_t *l, int col, int x, int w,
+                                             int row, int y, enum TxfmMode tx,
+                                             int p, int ss_h, int ss_v, int bytesperpixel)
+{
+    int have_top = row > 0 || y > 0;
+    int have_left = col > s->tiling.tile_col_start || x > 0;
+    int have_right = x < w - 1;
+    int bpp = s->bpp;
+    static const uint8_t mode_conv[10][2 /* have_left */][2 /* have_top */] = {
+        [VERT_PRED]            = { { DC_127_PRED,          VERT_PRED },
+                                   { DC_127_PRED,          VERT_PRED } },
+        [HOR_PRED]             = { { DC_129_PRED,          DC_129_PRED },
+                                   { HOR_PRED,             HOR_PRED } },
+        [DC_PRED]              = { { DC_128_PRED,          TOP_DC_PRED },
+                                   { LEFT_DC_PRED,         DC_PRED } },
+        [DIAG_DOWN_LEFT_PRED]  = { { DC_127_PRED,          DIAG_DOWN_LEFT_PRED },
+                                   { DC_127_PRED,          DIAG_DOWN_LEFT_PRED } },
+        [DIAG_DOWN_RIGHT_PRED] = { { DIAG_DOWN_RIGHT_PRED, DIAG_DOWN_RIGHT_PRED },
+                                   { DIAG_DOWN_RIGHT_PRED, DIAG_DOWN_RIGHT_PRED } },
+        [VERT_RIGHT_PRED]      = { { VERT_RIGHT_PRED,      VERT_RIGHT_PRED },
+                                   { VERT_RIGHT_PRED,      VERT_RIGHT_PRED } },
+        [HOR_DOWN_PRED]        = { { HOR_DOWN_PRED,        HOR_DOWN_PRED },
+                                   { HOR_DOWN_PRED,        HOR_DOWN_PRED } },
+        [VERT_LEFT_PRED]       = { { DC_127_PRED,          VERT_LEFT_PRED },
+                                   { DC_127_PRED,          VERT_LEFT_PRED } },
+        [HOR_UP_PRED]          = { { DC_129_PRED,          DC_129_PRED },
+                                   { HOR_UP_PRED,          HOR_UP_PRED } },
+        [TM_VP8_PRED]          = { { DC_129_PRED,          VERT_PRED },
+                                   { HOR_PRED,             TM_VP8_PRED } },
+    };
+    static const struct {
+        uint8_t needs_left:1;
+        uint8_t needs_top:1;
+        uint8_t needs_topleft:1;
+        uint8_t needs_topright:1;
+        uint8_t invert_left:1;
+    } edges[N_INTRA_PRED_MODES] = {
+        [VERT_PRED]            = { .needs_top  = 1 },
+        [HOR_PRED]             = { .needs_left = 1 },
+        [DC_PRED]              = { .needs_top  = 1, .needs_left = 1 },
+        [DIAG_DOWN_LEFT_PRED]  = { .needs_top  = 1, .needs_topright = 1 },
+        [DIAG_DOWN_RIGHT_PRED] = { .needs_left = 1, .needs_top = 1, .needs_topleft = 1 },
+        [VERT_RIGHT_PRED]      = { .needs_left = 1, .needs_top = 1, .needs_topleft = 1 },
+        [HOR_DOWN_PRED]        = { .needs_left = 1, .needs_top = 1, .needs_topleft = 1 },
+        [VERT_LEFT_PRED]       = { .needs_top  = 1, .needs_topright = 1 },
+        [HOR_UP_PRED]          = { .needs_left = 1, .invert_left = 1 },
+        [TM_VP8_PRED]          = { .needs_left = 1, .needs_top = 1, .needs_topleft = 1 },
+        [LEFT_DC_PRED]         = { .needs_left = 1 },
+        [TOP_DC_PRED]          = { .needs_top  = 1 },
+        [DC_128_PRED]          = { 0 },
+        [DC_127_PRED]          = { 0 },
+        [DC_129_PRED]          = { 0 }
+    };
+
+    av_assert2(mode >= 0 && mode < 10);
+    mode = mode_conv[mode][have_left][have_top];
+    if (edges[mode].needs_top) {
+        uint8_t *top, *topleft;
+        int n_px_need = 4 << tx, n_px_have = (((s->cols - col) << !ss_h) - x) * 4;
+        int n_px_need_tr = 0;
+
+        if (tx == TX_4X4 && edges[mode].needs_topright && have_right)
+            n_px_need_tr = 4;
+
+        // if top of sb64-row, use s->intra_pred_data[] instead of
+        // dst[-stride] for intra prediction (it contains pre- instead of
+        // post-loopfilter data)
+        if (have_top) {
+            top = !(row & 7) && !y ?
+                s->intra_pred_data[p] + (col * (8 >> ss_h) + x * 4) * bytesperpixel :
+                y == 0 ? &dst_edge[-stride_edge] : &dst_inner[-stride_inner];
+            if (have_left)
+                topleft = !(row & 7) && !y ?
+                    s->intra_pred_data[p] + (col * (8 >> ss_h) + x * 4) * bytesperpixel :
+                    y == 0 || x == 0 ? &dst_edge[-stride_edge] :
+                    &dst_inner[-stride_inner];
+        }
+
+        if (have_top &&
+            (!edges[mode].needs_topleft || (have_left && top == topleft)) &&
+            (tx != TX_4X4 || !edges[mode].needs_topright || have_right) &&
+            n_px_need + n_px_need_tr <= n_px_have) {
+            *a = top;
+        } else {
+            if (have_top) {
+                if (n_px_need <= n_px_have) {
+                    memcpy(*a, top, n_px_need * bytesperpixel);
+                } else {
+#define memset_bpp(c, i1, v, i2, num) do { \
+    if (bytesperpixel == 1) { \
+        memset(&(c)[(i1)], (v)[(i2)], (num)); \
+    } else { \
+        int n, val = AV_RN16A(&(v)[(i2) * 2]); \
+        for (n = 0; n < (num); n++) { \
+            AV_WN16A(&(c)[((i1) + n) * 2], val); \
+        } \
+    } \
+} while (0)
+                    memcpy(*a, top, n_px_have * bytesperpixel);
+                    memset_bpp(*a, n_px_have, (*a), n_px_have - 1, n_px_need - n_px_have);
+                }
+            } else {
+#define memset_val(c, val, num) do { \
+    if (bytesperpixel == 1) { \
+        memset((c), (val), (num)); \
+    } else { \
+        int n; \
+        for (n = 0; n < (num); n++) { \
+            AV_WN16A(&(c)[n * 2], (val)); \
+        } \
+    } \
+} while (0)
+                memset_val(*a, (128 << (bpp - 8)) - 1, n_px_need);
+            }
+            if (edges[mode].needs_topleft) {
+                if (have_left && have_top) {
+#define assign_bpp(c, i1, v, i2) do { \
+    if (bytesperpixel == 1) { \
+        (c)[(i1)] = (v)[(i2)]; \
+    } else { \
+        AV_COPY16(&(c)[(i1) * 2], &(v)[(i2) * 2]); \
+    } \
+} while (0)
+                    assign_bpp(*a, -1, topleft, -1);
+                } else {
+#define assign_val(c, i, v) do { \
+    if (bytesperpixel == 1) { \
+        (c)[(i)] = (v); \
+    } else { \
+        AV_WN16A(&(c)[(i) * 2], (v)); \
+    } \
+} while (0)
+                    assign_val((*a), -1, (128 << (bpp - 8)) + (have_top ? +1 : -1));
+                }
+            }
+            if (tx == TX_4X4 && edges[mode].needs_topright) {
+                if (have_top && have_right &&
+                    n_px_need + n_px_need_tr <= n_px_have) {
+                    memcpy(&(*a)[4 * bytesperpixel], &top[4 * bytesperpixel], 4 * bytesperpixel);
+                } else {
+                    memset_bpp(*a, 4, *a, 3, 4);
+                }
+            }
+        }
+    }
+    if (edges[mode].needs_left) {
+        if (have_left) {
+            int n_px_need = 4 << tx, i, n_px_have = (((s->rows - row) << !ss_v) - y) * 4;
+            uint8_t *dst = x == 0 ? dst_edge : dst_inner;
+            ptrdiff_t stride = x == 0 ? stride_edge : stride_inner;
+
+            if (edges[mode].invert_left) {
+                if (n_px_need <= n_px_have) {
+                    for (i = 0; i < n_px_need; i++)
+                        assign_bpp(l, i, &dst[i * stride], -1);
+                } else {
+                    for (i = 0; i < n_px_have; i++)
+                        assign_bpp(l, i, &dst[i * stride], -1);
+                    memset_bpp(l, n_px_have, l, n_px_have - 1, n_px_need - n_px_have);
+                }
+            } else {
+                if (n_px_need <= n_px_have) {
+                    for (i = 0; i < n_px_need; i++)
+                        assign_bpp(l, n_px_need - 1 - i, &dst[i * stride], -1);
+                } else {
+                    for (i = 0; i < n_px_have; i++)
+                        assign_bpp(l, n_px_need - 1 - i, &dst[i * stride], -1);
+                    memset_bpp(l, 0, l, n_px_need - n_px_have, n_px_need - n_px_have);
+                }
+            }
+        } else {
+            memset_val(l, (128 << (bpp - 8)) + 1, 4 << tx);
+        }
+    }
+
+    return mode;
+}
+
+static av_always_inline void intra_recon(AVCodecContext *ctx, ptrdiff_t y_off,
+                                         ptrdiff_t uv_off, int bytesperpixel)
+{
+    VP9Context *s = ctx->priv_data;
+    VP9Block *b = s->b;
+    int row = s->row, col = s->col;
+    int w4 = bwh_tab[1][b->bs][0] << 1, step1d = 1 << b->tx, n;
+    int h4 = bwh_tab[1][b->bs][1] << 1, x, y, step = 1 << (b->tx * 2);
+    int end_x = FFMIN(2 * (s->cols - col), w4);
+    int end_y = FFMIN(2 * (s->rows - row), h4);
+    int tx = 4 * s->lossless + b->tx, uvtx = b->uvtx + 4 * s->lossless;
+    int uvstep1d = 1 << b->uvtx, p;
+    uint8_t *dst = s->dst[0], *dst_r = s->frames[CUR_FRAME].tf.f->data[0] + y_off;
+    LOCAL_ALIGNED_32(uint8_t, a_buf, [96]);
+    LOCAL_ALIGNED_32(uint8_t, l, [64]);
+
+    for (n = 0, y = 0; y < end_y; y += step1d) {
+        uint8_t *ptr = dst, *ptr_r = dst_r;
+        for (x = 0; x < end_x; x += step1d, ptr += 4 * step1d * bytesperpixel,
+                               ptr_r += 4 * step1d * bytesperpixel, n += step) {
+            int mode = b->mode[b->bs > BS_8x8 && b->tx == TX_4X4 ?
+                               y * 2 + x : 0];
+            uint8_t *a = &a_buf[32];
+            enum TxfmType txtp = vp9_intra_txfm_type[mode];
+            int eob = b->skip ? 0 : b->tx > TX_8X8 ? AV_RN16A(&s->eob[n]) : s->eob[n];
+
+            mode = check_intra_mode(s, mode, &a, ptr_r,
+                                    s->frames[CUR_FRAME].tf.f->linesize[0],
+                                    ptr, s->y_stride, l,
+                                    col, x, w4, row, y, b->tx, 0, 0, 0, bytesperpixel);
+            s->dsp.intra_pred[b->tx][mode](ptr, s->y_stride, l, a);
+            if (eob)
+                s->dsp.itxfm_add[tx][txtp](ptr, s->y_stride,
+                                           s->block + 16 * n * bytesperpixel, eob);
+        }
+        dst_r += 4 * step1d * s->frames[CUR_FRAME].tf.f->linesize[0];
+        dst   += 4 * step1d * s->y_stride;
+    }
+
+    // U/V
+    w4 >>= s->ss_h;
+    end_x >>= s->ss_h;
+    end_y >>= s->ss_v;
+    step = 1 << (b->uvtx * 2);
+    for (p = 0; p < 2; p++) {
+        dst   = s->dst[1 + p];
+        dst_r = s->frames[CUR_FRAME].tf.f->data[1 + p] + uv_off;
+        for (n = 0, y = 0; y < end_y; y += uvstep1d) {
+            uint8_t *ptr = dst, *ptr_r = dst_r;
+            for (x = 0; x < end_x; x += uvstep1d, ptr += 4 * uvstep1d * bytesperpixel,
+                                   ptr_r += 4 * uvstep1d * bytesperpixel, n += step) {
+                int mode = b->uvmode;
+                uint8_t *a = &a_buf[32];
+                int eob = b->skip ? 0 : b->uvtx > TX_8X8 ? AV_RN16A(&s->uveob[p][n]) : s->uveob[p][n];
+
+                mode = check_intra_mode(s, mode, &a, ptr_r,
+                                        s->frames[CUR_FRAME].tf.f->linesize[1],
+                                        ptr, s->uv_stride, l, col, x, w4, row, y,
+                                        b->uvtx, p + 1, s->ss_h, s->ss_v, bytesperpixel);
+                s->dsp.intra_pred[b->uvtx][mode](ptr, s->uv_stride, l, a);
+                if (eob)
+                    s->dsp.itxfm_add[uvtx][DCT_DCT](ptr, s->uv_stride,
+                                                    s->uvblock[p] + 16 * n * bytesperpixel, eob);
+            }
+            dst_r += 4 * uvstep1d * s->frames[CUR_FRAME].tf.f->linesize[1];
+            dst   += 4 * uvstep1d * s->uv_stride;
+        }
+    }
+}
+
+static void intra_recon_8bpp(AVCodecContext *ctx, ptrdiff_t y_off, ptrdiff_t uv_off)
+{
+    intra_recon(ctx, y_off, uv_off, 1);
+}
+
+static void intra_recon_16bpp(AVCodecContext *ctx, ptrdiff_t y_off, ptrdiff_t uv_off)
+{
+    intra_recon(ctx, y_off, uv_off, 2);
+}
+
+static av_always_inline void mc_luma_scaled(VP9Context *s, vp9_scaled_mc_func smc,
+                                            uint8_t *dst, ptrdiff_t dst_stride,
+                                            const uint8_t *ref, ptrdiff_t ref_stride,
+                                            ThreadFrame *ref_frame,
+                                            ptrdiff_t y, ptrdiff_t x, const VP56mv *in_mv,
+                                            int px, int py, int pw, int ph,
+                                            int bw, int bh, int w, int h, int bytesperpixel,
+                                            const uint16_t *scale, const uint8_t *step)
+{
+#define scale_mv(n, dim) (((int64_t)(n) * scale[dim]) >> 14)
+    int mx, my;
+    int refbw_m1, refbh_m1;
+    int th;
+    VP56mv mv;
+
+    mv.x = av_clip(in_mv->x, -(x + pw - px + 4) << 3, (s->cols * 8 - x + px + 3) << 3);
+    mv.y = av_clip(in_mv->y, -(y + ph - py + 4) << 3, (s->rows * 8 - y + py + 3) << 3);
+    // BUG libvpx seems to scale the two components separately. This introduces
+    // rounding errors but we have to reproduce them to be exactly compatible
+    // with the output from libvpx...
+    mx = scale_mv(mv.x * 2, 0) + scale_mv(x * 16, 0);
+    my = scale_mv(mv.y * 2, 1) + scale_mv(y * 16, 1);
+
+    y = my >> 4;
+    x = mx >> 4;
+    ref += y * ref_stride + x * bytesperpixel;
+    mx &= 15;
+    my &= 15;
+    refbw_m1 = ((bw - 1) * step[0] + mx) >> 4;
+    refbh_m1 = ((bh - 1) * step[1] + my) >> 4;
+    // FIXME bilinear filter only needs 0/1 pixels, not 3/4
+    // we use +7 because the last 7 pixels of each sbrow can be changed in
+    // the longest loopfilter of the next sbrow
+    th = (y + refbh_m1 + 4 + 7) >> 6;
+    ff_thread_await_progress(ref_frame, FFMAX(th, 0), 0);
+    if (x < 3 || y < 3 || x + 4 >= w - refbw_m1 || y + 4 >= h - refbh_m1) {
+        s->vdsp.emulated_edge_mc(s->edge_emu_buffer,
+                                 ref - 3 * ref_stride - 3 * bytesperpixel,
+                                 288, ref_stride,
+                                 refbw_m1 + 8, refbh_m1 + 8,
+                                 x - 3, y - 3, w, h);
+        ref = s->edge_emu_buffer + 3 * 288 + 3 * bytesperpixel;
+        ref_stride = 288;
+    }
+    smc(dst, dst_stride, ref, ref_stride, bh, mx, my, step[0], step[1]);
+}
+
+static av_always_inline void mc_chroma_scaled(VP9Context *s, vp9_scaled_mc_func smc,
+                                              uint8_t *dst_u, uint8_t *dst_v,
+                                              ptrdiff_t dst_stride,
+                                              const uint8_t *ref_u, ptrdiff_t src_stride_u,
+                                              const uint8_t *ref_v, ptrdiff_t src_stride_v,
+                                              ThreadFrame *ref_frame,
+                                              ptrdiff_t y, ptrdiff_t x, const VP56mv *in_mv,
+                                              int px, int py, int pw, int ph,
+                                              int bw, int bh, int w, int h, int bytesperpixel,
+                                              const uint16_t *scale, const uint8_t *step)
+{
+    int mx, my;
+    int refbw_m1, refbh_m1;
+    int th;
+    VP56mv mv;
+
+    if (s->ss_h) {
+        // BUG https://code.google.com/p/webm/issues/detail?id=820
+        mv.x = av_clip(in_mv->x, -(x + pw - px + 4) << 4, (s->cols * 4 - x + px + 3) << 4);
+        mx = scale_mv(mv.x, 0) + (scale_mv(x * 16, 0) & ~15) + (scale_mv(x * 32, 0) & 15);
+    } else {
+        mv.x = av_clip(in_mv->x, -(x + pw - px + 4) << 3, (s->cols * 8 - x + px + 3) << 3);
+        mx = scale_mv(mv.x << 1, 0) + scale_mv(x * 16, 0);
+    }
+    if (s->ss_v) {
+        // BUG https://code.google.com/p/webm/issues/detail?id=820
+        mv.y = av_clip(in_mv->y, -(y + ph - py + 4) << 4, (s->rows * 4 - y + py + 3) << 4);
+        my = scale_mv(mv.y, 1) + (scale_mv(y * 16, 1) & ~15) + (scale_mv(y * 32, 1) & 15);
+    } else {
+        mv.y = av_clip(in_mv->y, -(y + ph - py + 4) << 3, (s->rows * 8 - y + py + 3) << 3);
+        my = scale_mv(mv.y << 1, 1) + scale_mv(y * 16, 1);
+    }
+#undef scale_mv
+    y = my >> 4;
+    x = mx >> 4;
+    ref_u += y * src_stride_u + x * bytesperpixel;
+    ref_v += y * src_stride_v + x * bytesperpixel;
+    mx &= 15;
+    my &= 15;
+    refbw_m1 = ((bw - 1) * step[0] + mx) >> 4;
+    refbh_m1 = ((bh - 1) * step[1] + my) >> 4;
+    // FIXME bilinear filter only needs 0/1 pixels, not 3/4
+    // we use +7 because the last 7 pixels of each sbrow can be changed in
+    // the longest loopfilter of the next sbrow
+    th = (y + refbh_m1 + 4 + 7) >> (6 - s->ss_v);
+    ff_thread_await_progress(ref_frame, FFMAX(th, 0), 0);
+    if (x < 3 || y < 3 || x + 4 >= w - refbw_m1 || y + 4 >= h - refbh_m1) {
+        s->vdsp.emulated_edge_mc(s->edge_emu_buffer,
+                                 ref_u - 3 * src_stride_u - 3 * bytesperpixel,
+                                 288, src_stride_u,
+                                 refbw_m1 + 8, refbh_m1 + 8,
+                                 x - 3, y - 3, w, h);
+        ref_u = s->edge_emu_buffer + 3 * 288 + 3 * bytesperpixel;
+        smc(dst_u, dst_stride, ref_u, 288, bh, mx, my, step[0], step[1]);
+
+        s->vdsp.emulated_edge_mc(s->edge_emu_buffer,
+                                 ref_v - 3 * src_stride_v - 3 * bytesperpixel,
+                                 288, src_stride_v,
+                                 refbw_m1 + 8, refbh_m1 + 8,
+                                 x - 3, y - 3, w, h);
+        ref_v = s->edge_emu_buffer + 3 * 288 + 3 * bytesperpixel;
+        smc(dst_v, dst_stride, ref_v, 288, bh, mx, my, step[0], step[1]);
+    } else {
+        smc(dst_u, dst_stride, ref_u, src_stride_u, bh, mx, my, step[0], step[1]);
+        smc(dst_v, dst_stride, ref_v, src_stride_v, bh, mx, my, step[0], step[1]);
+    }
+}
+
+#define mc_luma_dir(s, mc, dst, dst_ls, src, src_ls, tref, row, col, mv, \
+                    px, py, pw, ph, bw, bh, w, h, i) \
+    mc_luma_scaled(s, s->dsp.s##mc, dst, dst_ls, src, src_ls, tref, row, col, \
+                   mv, px, py, pw, ph, bw, bh, w, h, bytesperpixel, \
+                   s->mvscale[b->ref[i]], s->mvstep[b->ref[i]])
+#define mc_chroma_dir(s, mc, dstu, dstv, dst_ls, srcu, srcu_ls, srcv, srcv_ls, tref, \
+                      row, col, mv, px, py, pw, ph, bw, bh, w, h, i) \
+    mc_chroma_scaled(s, s->dsp.s##mc, dstu, dstv, dst_ls, srcu, srcu_ls, srcv, srcv_ls, tref, \
+                     row, col, mv, px, py, pw, ph, bw, bh, w, h, bytesperpixel, \
+                     s->mvscale[b->ref[i]], s->mvstep[b->ref[i]])
+#define SCALED 1
+#define FN(x) x##_scaled_8bpp
+#define BYTES_PER_PIXEL 1
+#include "vp9_mc_template.c"
+#undef FN
+#undef BYTES_PER_PIXEL
+#define FN(x) x##_scaled_16bpp
+#define BYTES_PER_PIXEL 2
+#include "vp9_mc_template.c"
+#undef mc_luma_dir
+#undef mc_chroma_dir
+#undef FN
+#undef BYTES_PER_PIXEL
+#undef SCALED
+
+static av_always_inline void mc_luma_unscaled(VP9Context *s, vp9_mc_func (*mc)[2],
+                                              uint8_t *dst, ptrdiff_t dst_stride,
+                                              const uint8_t *ref, ptrdiff_t ref_stride,
+                                              ThreadFrame *ref_frame,
+                                              ptrdiff_t y, ptrdiff_t x, const VP56mv *mv,
+                                              int bw, int bh, int w, int h, int bytesperpixel)
+{
+    int mx = mv->x, my = mv->y, th;
+
+    y += my >> 3;
+    x += mx >> 3;
+    ref += y * ref_stride + x * bytesperpixel;
+    mx &= 7;
+    my &= 7;
+    // FIXME bilinear filter only needs 0/1 pixels, not 3/4
+    // we use +7 because the last 7 pixels of each sbrow can be changed in
+    // the longest loopfilter of the next sbrow
+    th = (y + bh + 4 * !!my + 7) >> 6;
+    ff_thread_await_progress(ref_frame, FFMAX(th, 0), 0);
+    if (x < !!mx * 3 || y < !!my * 3 ||
+        x + !!mx * 4 > w - bw || y + !!my * 4 > h - bh) {
+        s->vdsp.emulated_edge_mc(s->edge_emu_buffer,
+                                 ref - !!my * 3 * ref_stride - !!mx * 3 * bytesperpixel,
+                                 160, ref_stride,
+                                 bw + !!mx * 7, bh + !!my * 7,
+                                 x - !!mx * 3, y - !!my * 3, w, h);
+        ref = s->edge_emu_buffer + !!my * 3 * 160 + !!mx * 3 * bytesperpixel;
+        ref_stride = 160;
+    }
+    mc[!!mx][!!my](dst, dst_stride, ref, ref_stride, bh, mx << 1, my << 1);
+}
+
+static av_always_inline void mc_chroma_unscaled(VP9Context *s, vp9_mc_func (*mc)[2],
+                                                uint8_t *dst_u, uint8_t *dst_v,
+                                                ptrdiff_t dst_stride,
+                                                const uint8_t *ref_u, ptrdiff_t src_stride_u,
+                                                const uint8_t *ref_v, ptrdiff_t src_stride_v,
+                                                ThreadFrame *ref_frame,
+                                                ptrdiff_t y, ptrdiff_t x, const VP56mv *mv,
+                                                int bw, int bh, int w, int h, int bytesperpixel)
+{
+    int mx = mv->x << !s->ss_h, my = mv->y << !s->ss_v, th;
+
+    y += my >> 4;
+    x += mx >> 4;
+    ref_u += y * src_stride_u + x * bytesperpixel;
+    ref_v += y * src_stride_v + x * bytesperpixel;
+    mx &= 15;
+    my &= 15;
+    // FIXME bilinear filter only needs 0/1 pixels, not 3/4
+    // we use +7 because the last 7 pixels of each sbrow can be changed in
+    // the longest loopfilter of the next sbrow
+    th = (y + bh + 4 * !!my + 7) >> (6 - s->ss_v);
+    ff_thread_await_progress(ref_frame, FFMAX(th, 0), 0);
+    if (x < !!mx * 3 || y < !!my * 3 ||
+        x + !!mx * 4 > w - bw || y + !!my * 4 > h - bh) {
+        s->vdsp.emulated_edge_mc(s->edge_emu_buffer,
+                                 ref_u - !!my * 3 * src_stride_u - !!mx * 3 * bytesperpixel,
+                                 160, src_stride_u,
+                                 bw + !!mx * 7, bh + !!my * 7,
+                                 x - !!mx * 3, y - !!my * 3, w, h);
+        ref_u = s->edge_emu_buffer + !!my * 3 * 160 + !!mx * 3 * bytesperpixel;
+        mc[!!mx][!!my](dst_u, dst_stride, ref_u, 160, bh, mx, my);
+
+        s->vdsp.emulated_edge_mc(s->edge_emu_buffer,
+                                 ref_v - !!my * 3 * src_stride_v - !!mx * 3 * bytesperpixel,
+                                 160, src_stride_v,
+                                 bw + !!mx * 7, bh + !!my * 7,
+                                 x - !!mx * 3, y - !!my * 3, w, h);
+        ref_v = s->edge_emu_buffer + !!my * 3 * 160 + !!mx * 3 * bytesperpixel;
+        mc[!!mx][!!my](dst_v, dst_stride, ref_v, 160, bh, mx, my);
+    } else {
+        mc[!!mx][!!my](dst_u, dst_stride, ref_u, src_stride_u, bh, mx, my);
+        mc[!!mx][!!my](dst_v, dst_stride, ref_v, src_stride_v, bh, mx, my);
+    }
+}
+
+#define mc_luma_dir(s, mc, dst, dst_ls, src, src_ls, tref, row, col, mv, \
+                    px, py, pw, ph, bw, bh, w, h, i) \
+    mc_luma_unscaled(s, s->dsp.mc, dst, dst_ls, src, src_ls, tref, row, col, \
+                     mv, bw, bh, w, h, bytesperpixel)
+#define mc_chroma_dir(s, mc, dstu, dstv, dst_ls, srcu, srcu_ls, srcv, srcv_ls, tref, \
+                      row, col, mv, px, py, pw, ph, bw, bh, w, h, i) \
+    mc_chroma_unscaled(s, s->dsp.mc, dstu, dstv, dst_ls, srcu, srcu_ls, srcv, srcv_ls, tref, \
+                       row, col, mv, bw, bh, w, h, bytesperpixel)
+#define SCALED 0
+#define FN(x) x##_8bpp
+#define BYTES_PER_PIXEL 1
+#include "vp9_mc_template.c"
+#undef FN
+#undef BYTES_PER_PIXEL
+#define FN(x) x##_16bpp
+#define BYTES_PER_PIXEL 2
+#include "vp9_mc_template.c"
+#undef mc_luma_dir_dir
+#undef mc_chroma_dir_dir
+#undef FN
+#undef BYTES_PER_PIXEL
+#undef SCALED
+
+static av_always_inline void inter_recon(AVCodecContext *ctx, int bytesperpixel)
+{
+    VP9Context *s = ctx->priv_data;
+    VP9Block *b = s->b;
+    int row = s->row, col = s->col;
+
+    if (s->mvscale[b->ref[0]][0] || (b->comp && s->mvscale[b->ref[1]][0])) {
+        if (bytesperpixel == 1) {
+            inter_pred_scaled_8bpp(ctx);
+        } else {
+            inter_pred_scaled_16bpp(ctx);
+        }
+    } else {
+        if (bytesperpixel == 1) {
+            inter_pred_8bpp(ctx);
+        } else {
+            inter_pred_16bpp(ctx);
+        }
+    }
+    if (!b->skip) {
+        /* mostly copied intra_recon() */
+
+        int w4 = bwh_tab[1][b->bs][0] << 1, step1d = 1 << b->tx, n;
+        int h4 = bwh_tab[1][b->bs][1] << 1, x, y, step = 1 << (b->tx * 2);
+        int end_x = FFMIN(2 * (s->cols - col), w4);
+        int end_y = FFMIN(2 * (s->rows - row), h4);
+        int tx = 4 * s->lossless + b->tx, uvtx = b->uvtx + 4 * s->lossless;
+        int uvstep1d = 1 << b->uvtx, p;
+        uint8_t *dst = s->dst[0];
+
+        // y itxfm add
+        for (n = 0, y = 0; y < end_y; y += step1d) {
+            uint8_t *ptr = dst;
+            for (x = 0; x < end_x; x += step1d,
+                 ptr += 4 * step1d * bytesperpixel, n += step) {
+                int eob = b->tx > TX_8X8 ? AV_RN16A(&s->eob[n]) : s->eob[n];
+
+                if (eob)
+                    s->dsp.itxfm_add[tx][DCT_DCT](ptr, s->y_stride,
+                                                  s->block + 16 * n * bytesperpixel, eob);
+            }
+            dst += 4 * s->y_stride * step1d;
+        }
+
+        // uv itxfm add
+        end_x >>= s->ss_h;
+        end_y >>= s->ss_v;
+        step = 1 << (b->uvtx * 2);
+        for (p = 0; p < 2; p++) {
+            dst = s->dst[p + 1];
+            for (n = 0, y = 0; y < end_y; y += uvstep1d) {
+                uint8_t *ptr = dst;
+                for (x = 0; x < end_x; x += uvstep1d,
+                     ptr += 4 * uvstep1d * bytesperpixel, n += step) {
+                    int eob = b->uvtx > TX_8X8 ? AV_RN16A(&s->uveob[p][n]) : s->uveob[p][n];
+
+                    if (eob)
+                        s->dsp.itxfm_add[uvtx][DCT_DCT](ptr, s->uv_stride,
+                                                        s->uvblock[p] + 16 * n * bytesperpixel, eob);
+                }
+                dst += 4 * uvstep1d * s->uv_stride;
+            }
+        }
+    }
+}
+
+static void inter_recon_8bpp(AVCodecContext *ctx)
+{
+    inter_recon(ctx, 1);
+}
+
+static void inter_recon_16bpp(AVCodecContext *ctx)
+{
+    inter_recon(ctx, 2);
+}
+
+static av_always_inline void mask_edges(uint8_t (*mask)[8][4], int ss_h, int ss_v,
+                                        int row_and_7, int col_and_7,
+                                        int w, int h, int col_end, int row_end,
+                                        enum TxfmMode tx, int skip_inter)
+{
+    static const unsigned wide_filter_col_mask[2] = { 0x11, 0x01 };
+    static const unsigned wide_filter_row_mask[2] = { 0x03, 0x07 };
+
+    // FIXME I'm pretty sure all loops can be replaced by a single LUT if
+    // we make VP9Filter.mask uint64_t (i.e. row/col all single variable)
+    // and make the LUT 5-indexed (bl, bp, is_uv, tx and row/col), and then
+    // use row_and_7/col_and_7 as shifts (1*col_and_7+8*row_and_7)
+
+    // the intended behaviour of the vp9 loopfilter is to work on 8-pixel
+    // edges. This means that for UV, we work on two subsampled blocks at
+    // a time, and we only use the topleft block's mode information to set
+    // things like block strength. Thus, for any block size smaller than
+    // 16x16, ignore the odd portion of the block.
+    if (tx == TX_4X4 && (ss_v | ss_h)) {
+        if (h == ss_v) {
+            if (row_and_7 & 1)
+                return;
+            if (!row_end)
+                h += 1;
+        }
+        if (w == ss_h) {
+            if (col_and_7 & 1)
+                return;
+            if (!col_end)
+                w += 1;
+        }
+    }
+
+    if (tx == TX_4X4 && !skip_inter) {
+        int t = 1 << col_and_7, m_col = (t << w) - t, y;
+        // on 32-px edges, use the 8-px wide loopfilter; else, use 4-px wide
+        int m_row_8 = m_col & wide_filter_col_mask[ss_h], m_row_4 = m_col - m_row_8;
+
+        for (y = row_and_7; y < h + row_and_7; y++) {
+            int col_mask_id = 2 - !(y & wide_filter_row_mask[ss_v]);
+
+            mask[0][y][1] |= m_row_8;
+            mask[0][y][2] |= m_row_4;
+            // for odd lines, if the odd col is not being filtered,
+            // skip odd row also:
+            // .---. <-- a
+            // |   |
+            // |___| <-- b
+            // ^   ^
+            // c   d
+            //
+            // if a/c are even row/col and b/d are odd, and d is skipped,
+            // e.g. right edge of size-66x66.webm, then skip b also (bug)
+            if ((ss_h & ss_v) && (col_end & 1) && (y & 1)) {
+                mask[1][y][col_mask_id] |= (t << (w - 1)) - t;
+            } else {
+                mask[1][y][col_mask_id] |= m_col;
+            }
+            if (!ss_h)
+                mask[0][y][3] |= m_col;
+            if (!ss_v) {
+                if (ss_h && (col_end & 1))
+                    mask[1][y][3] |= (t << (w - 1)) - t;
+                else
+                    mask[1][y][3] |= m_col;
+            }
+        }
+    } else {
+        int y, t = 1 << col_and_7, m_col = (t << w) - t;
+
+        if (!skip_inter) {
+            int mask_id = (tx == TX_8X8);
+            static const unsigned masks[4] = { 0xff, 0x55, 0x11, 0x01 };
+            int l2 = tx + ss_h - 1, step1d;
+            int m_row = m_col & masks[l2];
+
+            // at odd UV col/row edges tx16/tx32 loopfilter edges, force
+            // 8wd loopfilter to prevent going off the visible edge.
+            if (ss_h && tx > TX_8X8 && (w ^ (w - 1)) == 1) {
+                int m_row_16 = ((t << (w - 1)) - t) & masks[l2];
+                int m_row_8 = m_row - m_row_16;
+
+                for (y = row_and_7; y < h + row_and_7; y++) {
+                    mask[0][y][0] |= m_row_16;
+                    mask[0][y][1] |= m_row_8;
+                }
+            } else {
+                for (y = row_and_7; y < h + row_and_7; y++)
+                    mask[0][y][mask_id] |= m_row;
+            }
+
+            l2 = tx + ss_v - 1;
+            step1d = 1 << l2;
+            if (ss_v && tx > TX_8X8 && (h ^ (h - 1)) == 1) {
+                for (y = row_and_7; y < h + row_and_7 - 1; y += step1d)
+                    mask[1][y][0] |= m_col;
+                if (y - row_and_7 == h - 1)
+                    mask[1][y][1] |= m_col;
+            } else {
+                for (y = row_and_7; y < h + row_and_7; y += step1d)
+                    mask[1][y][mask_id] |= m_col;
+            }
+        } else if (tx != TX_4X4) {
+            int mask_id;
+
+            mask_id = (tx == TX_8X8) || (h == ss_v);
+            mask[1][row_and_7][mask_id] |= m_col;
+            mask_id = (tx == TX_8X8) || (w == ss_h);
+            for (y = row_and_7; y < h + row_and_7; y++)
+                mask[0][y][mask_id] |= t;
+        } else {
+            int t8 = t & wide_filter_col_mask[ss_h], t4 = t - t8;
+
+            for (y = row_and_7; y < h + row_and_7; y++) {
+                mask[0][y][2] |= t4;
+                mask[0][y][1] |= t8;
+            }
+            mask[1][row_and_7][2 - !(row_and_7 & wide_filter_row_mask[ss_v])] |= m_col;
+        }
+    }
+}
+
+static void decode_b(AVCodecContext *ctx, int row, int col,
+                     struct VP9Filter *lflvl, ptrdiff_t yoff, ptrdiff_t uvoff,
+                     enum BlockLevel bl, enum BlockPartition bp)
+{
+    VP9Context *s = ctx->priv_data;
+    VP9Block *b = s->b;
+    enum BlockSize bs = bl * 3 + bp;
+    int bytesperpixel = s->bytesperpixel;
+    int w4 = bwh_tab[1][bs][0], h4 = bwh_tab[1][bs][1], lvl;
+    int emu[2];
+    AVFrame *f = s->frames[CUR_FRAME].tf.f;
+
+    s->row = row;
+    s->row7 = row & 7;
+    s->col = col;
+    s->col7 = col & 7;
+    s->min_mv.x = -(128 + col * 64);
+    s->min_mv.y = -(128 + row * 64);
+    s->max_mv.x = 128 + (s->cols - col - w4) * 64;
+    s->max_mv.y = 128 + (s->rows - row - h4) * 64;
+    if (s->pass < 2) {
+        b->bs = bs;
+        b->bl = bl;
+        b->bp = bp;
+        decode_mode(ctx);
+        b->uvtx = b->tx - ((s->ss_h && w4 * 2 == (1 << b->tx)) ||
+                           (s->ss_v && h4 * 2 == (1 << b->tx)));
+
+        if (!b->skip) {
+            int has_coeffs;
+
+            if (bytesperpixel == 1) {
+                has_coeffs = decode_coeffs_8bpp(ctx);
+            } else {
+                has_coeffs = decode_coeffs_16bpp(ctx);
+            }
+            if (!has_coeffs && b->bs <= BS_8x8 && !b->intra) {
+                b->skip = 1;
+                memset(&s->above_skip_ctx[col], 1, w4);
+                memset(&s->left_skip_ctx[s->row7], 1, h4);
+            }
+        } else {
+            int row7 = s->row7;
+
+#define SPLAT_ZERO_CTX(v, n) \
+    switch (n) { \
+    case 1:  v = 0;          break; \
+    case 2:  AV_ZERO16(&v);  break; \
+    case 4:  AV_ZERO32(&v);  break; \
+    case 8:  AV_ZERO64(&v);  break; \
+    case 16: AV_ZERO128(&v); break; \
+    }
+#define SPLAT_ZERO_YUV(dir, var, off, n, dir2) \
+    do { \
+        SPLAT_ZERO_CTX(s->dir##_y_##var[off * 2], n * 2); \
+        if (s->ss_##dir2) { \
+            SPLAT_ZERO_CTX(s->dir##_uv_##var[0][off], n); \
+            SPLAT_ZERO_CTX(s->dir##_uv_##var[1][off], n); \
+        } else { \
+            SPLAT_ZERO_CTX(s->dir##_uv_##var[0][off * 2], n * 2); \
+            SPLAT_ZERO_CTX(s->dir##_uv_##var[1][off * 2], n * 2); \
+        } \
+    } while (0)
+
+            switch (w4) {
+            case 1: SPLAT_ZERO_YUV(above, nnz_ctx, col, 1, h); break;
+            case 2: SPLAT_ZERO_YUV(above, nnz_ctx, col, 2, h); break;
+            case 4: SPLAT_ZERO_YUV(above, nnz_ctx, col, 4, h); break;
+            case 8: SPLAT_ZERO_YUV(above, nnz_ctx, col, 8, h); break;
+            }
+            switch (h4) {
+            case 1: SPLAT_ZERO_YUV(left, nnz_ctx, row7, 1, v); break;
+            case 2: SPLAT_ZERO_YUV(left, nnz_ctx, row7, 2, v); break;
+            case 4: SPLAT_ZERO_YUV(left, nnz_ctx, row7, 4, v); break;
+            case 8: SPLAT_ZERO_YUV(left, nnz_ctx, row7, 8, v); break;
+            }
+        }
+        if (s->pass == 1) {
+            s->b++;
+            s->block += w4 * h4 * 64 * bytesperpixel;
+            s->uvblock[0] += w4 * h4 * 64 * bytesperpixel >> (s->ss_h + s->ss_v);
+            s->uvblock[1] += w4 * h4 * 64 * bytesperpixel >> (s->ss_h + s->ss_v);
+            s->eob += 4 * w4 * h4;
+            s->uveob[0] += 4 * w4 * h4 >> (s->ss_h + s->ss_v);
+            s->uveob[1] += 4 * w4 * h4 >> (s->ss_h + s->ss_v);
+
+            return;
+        }
+    }
+
+    // emulated overhangs if the stride of the target buffer can't hold. This
+    // allows to support emu-edge and so on even if we have large block
+    // overhangs
+    emu[0] = (col + w4) * 8 > f->linesize[0] ||
+             (row + h4) > s->rows;
+    emu[1] = (col + w4) * 4 > f->linesize[1] ||
+             (row + h4) > s->rows;
+    if (emu[0]) {
+        s->dst[0] = s->tmp_y;
+        s->y_stride = 128;
+    } else {
+        s->dst[0] = f->data[0] + yoff;
+        s->y_stride = f->linesize[0];
+    }
+    if (emu[1]) {
+        s->dst[1] = s->tmp_uv[0];
+        s->dst[2] = s->tmp_uv[1];
+        s->uv_stride = 128;
+    } else {
+        s->dst[1] = f->data[1] + uvoff;
+        s->dst[2] = f->data[2] + uvoff;
+        s->uv_stride = f->linesize[1];
+    }
+    if (b->intra) {
+        if (s->bpp > 8) {
+            intra_recon_16bpp(ctx, yoff, uvoff);
+        } else {
+            intra_recon_8bpp(ctx, yoff, uvoff);
+        }
+    } else {
+        if (s->bpp > 8) {
+            inter_recon_16bpp(ctx);
+        } else {
+            inter_recon_8bpp(ctx);
+        }
+    }
+    if (emu[0]) {
+        int w = FFMIN(s->cols - col, w4) * 8, h = FFMIN(s->rows - row, h4) * 8, n, o = 0;
+
+        for (n = 0; o < w; n++) {
+            int bw = 64 >> n;
+
+            av_assert2(n <= 4);
+            if (w & bw) {
+                s->dsp.mc[n][0][0][0][0](f->data[0] + yoff + o, f->linesize[0],
+                                         s->tmp_y + o, 128, h, 0, 0);
+                o += bw * bytesperpixel;
+            }
+        }
+    }
+    if (emu[1]) {
+        int w = FFMIN(s->cols - col, w4) * 8 >> s->ss_h;
+        int h = FFMIN(s->rows - row, h4) * 8 >> s->ss_v, n, o = 0;
+
+        for (n = s->ss_h; o < w; n++) {
+            int bw = 64 >> n;
+
+            av_assert2(n <= 4);
+            if (w & bw) {
+                s->dsp.mc[n][0][0][0][0](f->data[1] + uvoff + o, f->linesize[1],
+                                         s->tmp_uv[0] + o, 128, h, 0, 0);
+                s->dsp.mc[n][0][0][0][0](f->data[2] + uvoff + o, f->linesize[2],
+                                         s->tmp_uv[1] + o, 128, h, 0, 0);
+                o += bw * bytesperpixel;
+            }
+        }
+    }
+
+    // pick filter level and find edges to apply filter to
+    if (s->filter.level &&
+        (lvl = s->segmentation.feat[b->seg_id].lflvl[b->intra ? 0 : b->ref[0] + 1]
+                                                    [b->mode[3] != ZEROMV]) > 0) {
+        int x_end = FFMIN(s->cols - col, w4), y_end = FFMIN(s->rows - row, h4);
+        int skip_inter = !b->intra && b->skip, col7 = s->col7, row7 = s->row7;
+
+        setctx_2d(&lflvl->level[row7 * 8 + col7], w4, h4, 8, lvl);
+        mask_edges(lflvl->mask[0], 0, 0, row7, col7, x_end, y_end, 0, 0, b->tx, skip_inter);
+        if (s->ss_h || s->ss_v)
+            mask_edges(lflvl->mask[1], s->ss_h, s->ss_v, row7, col7, x_end, y_end,
+                       s->cols & 1 && col + w4 >= s->cols ? s->cols & 7 : 0,
+                       s->rows & 1 && row + h4 >= s->rows ? s->rows & 7 : 0,
+                       b->uvtx, skip_inter);
+
+        if (!s->filter.lim_lut[lvl]) {
+            int sharp = s->filter.sharpness;
+            int limit = lvl;
+
+            if (sharp > 0) {
+                limit >>= (sharp + 3) >> 2;
+                limit = FFMIN(limit, 9 - sharp);
+            }
+            limit = FFMAX(limit, 1);
+
+            s->filter.lim_lut[lvl] = limit;
+            s->filter.mblim_lut[lvl] = 2 * (lvl + 2) + limit;
+        }
+    }
+
+    if (s->pass == 2) {
+        s->b++;
+        s->block += w4 * h4 * 64 * bytesperpixel;
+        s->uvblock[0] += w4 * h4 * 64 * bytesperpixel >> (s->ss_v + s->ss_h);
+        s->uvblock[1] += w4 * h4 * 64 * bytesperpixel >> (s->ss_v + s->ss_h);
+        s->eob += 4 * w4 * h4;
+        s->uveob[0] += 4 * w4 * h4 >> (s->ss_v + s->ss_h);
+        s->uveob[1] += 4 * w4 * h4 >> (s->ss_v + s->ss_h);
+    }
+}
+
+static void decode_sb(AVCodecContext *ctx, int row, int col, struct VP9Filter *lflvl,
+                      ptrdiff_t yoff, ptrdiff_t uvoff, enum BlockLevel bl)
+{
+    VP9Context *s = ctx->priv_data;
+    int c = ((s->above_partition_ctx[col] >> (3 - bl)) & 1) |
+            (((s->left_partition_ctx[row & 0x7] >> (3 - bl)) & 1) << 1);
+    const uint8_t *p = s->keyframe || s->intraonly ? vp9_default_kf_partition_probs[bl][c] :
+                                                     s->prob.p.partition[bl][c];
+    enum BlockPartition bp;
+    ptrdiff_t hbs = 4 >> bl;
+    AVFrame *f = s->frames[CUR_FRAME].tf.f;
+    ptrdiff_t y_stride = f->linesize[0], uv_stride = f->linesize[1];
+    int bytesperpixel = s->bytesperpixel;
+
+    if (bl == BL_8X8) {
+        bp = vp8_rac_get_tree(&s->c, vp9_partition_tree, p);
+        decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);
+    } else if (col + hbs < s->cols) { // FIXME why not <=?
+        if (row + hbs < s->rows) { // FIXME why not <=?
+            bp = vp8_rac_get_tree(&s->c, vp9_partition_tree, p);
+            switch (bp) {
+            case PARTITION_NONE:
+                decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);
+                break;
+            case PARTITION_H:
+                decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);
+                yoff  += hbs * 8 * y_stride;
+                uvoff += hbs * 8 * uv_stride >> s->ss_v;
+                decode_b(ctx, row + hbs, col, lflvl, yoff, uvoff, bl, bp);
+                break;
+            case PARTITION_V:
+                decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);
+                yoff  += hbs * 8 * bytesperpixel;
+                uvoff += hbs * 8 * bytesperpixel >> s->ss_h;
+                decode_b(ctx, row, col + hbs, lflvl, yoff, uvoff, bl, bp);
+                break;
+            case PARTITION_SPLIT:
+                decode_sb(ctx, row, col, lflvl, yoff, uvoff, bl + 1);
+                decode_sb(ctx, row, col + hbs, lflvl,
+                          yoff + 8 * hbs * bytesperpixel,
+                          uvoff + (8 * hbs * bytesperpixel >> s->ss_h), bl + 1);
+                yoff  += hbs * 8 * y_stride;
+                uvoff += hbs * 8 * uv_stride >> s->ss_v;
+                decode_sb(ctx, row + hbs, col, lflvl, yoff, uvoff, bl + 1);
+                decode_sb(ctx, row + hbs, col + hbs, lflvl,
+                          yoff + 8 * hbs * bytesperpixel,
+                          uvoff + (8 * hbs * bytesperpixel >> s->ss_h), bl + 1);
+                break;
+            default:
+                av_assert0(0);
+            }
+        } else if (vp56_rac_get_prob_branchy(&s->c, p[1])) {
+            bp = PARTITION_SPLIT;
+            decode_sb(ctx, row, col, lflvl, yoff, uvoff, bl + 1);
+            decode_sb(ctx, row, col + hbs, lflvl,
+                      yoff + 8 * hbs * bytesperpixel,
+                      uvoff + (8 * hbs * bytesperpixel >> s->ss_h), bl + 1);
+        } else {
+            bp = PARTITION_H;
+            decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);
+        }
+    } else if (row + hbs < s->rows) { // FIXME why not <=?
+        if (vp56_rac_get_prob_branchy(&s->c, p[2])) {
+            bp = PARTITION_SPLIT;
+            decode_sb(ctx, row, col, lflvl, yoff, uvoff, bl + 1);
+            yoff  += hbs * 8 * y_stride;
+            uvoff += hbs * 8 * uv_stride >> s->ss_v;
+            decode_sb(ctx, row + hbs, col, lflvl, yoff, uvoff, bl + 1);
+        } else {
+            bp = PARTITION_V;
+            decode_b(ctx, row, col, lflvl, yoff, uvoff, bl, bp);
+        }
+    } else {
+        bp = PARTITION_SPLIT;
+        decode_sb(ctx, row, col, lflvl, yoff, uvoff, bl + 1);
+    }
+    s->counts.partition[bl][c][bp]++;
+}
+
+static void decode_sb_mem(AVCodecContext *ctx, int row, int col, struct VP9Filter *lflvl,
+                          ptrdiff_t yoff, ptrdiff_t uvoff, enum BlockLevel bl)
+{
+    VP9Context *s = ctx->priv_data;
+    VP9Block *b = s->b;
+    ptrdiff_t hbs = 4 >> bl;
+    AVFrame *f = s->frames[CUR_FRAME].tf.f;
+    ptrdiff_t y_stride = f->linesize[0], uv_stride = f->linesize[1];
+    int bytesperpixel = s->bytesperpixel;
+
+    if (bl == BL_8X8) {
+        av_assert2(b->bl == BL_8X8);
+        decode_b(ctx, row, col, lflvl, yoff, uvoff, b->bl, b->bp);
+    } else if (s->b->bl == bl) {
+        decode_b(ctx, row, col, lflvl, yoff, uvoff, b->bl, b->bp);
+        if (b->bp == PARTITION_H && row + hbs < s->rows) {
+            yoff  += hbs * 8 * y_stride;
+            uvoff += hbs * 8 * uv_stride >> s->ss_v;
+            decode_b(ctx, row + hbs, col, lflvl, yoff, uvoff, b->bl, b->bp);
+        } else if (b->bp == PARTITION_V && col + hbs < s->cols) {
+            yoff  += hbs * 8 * bytesperpixel;
+            uvoff += hbs * 8 * bytesperpixel >> s->ss_h;
+            decode_b(ctx, row, col + hbs, lflvl, yoff, uvoff, b->bl, b->bp);
+        }
+    } else {
+        decode_sb_mem(ctx, row, col, lflvl, yoff, uvoff, bl + 1);
+        if (col + hbs < s->cols) { // FIXME why not <=?
+            if (row + hbs < s->rows) {
+                decode_sb_mem(ctx, row, col + hbs, lflvl, yoff + 8 * hbs * bytesperpixel,
+                              uvoff + (8 * hbs * bytesperpixel >> s->ss_h), bl + 1);
+                yoff  += hbs * 8 * y_stride;
+                uvoff += hbs * 8 * uv_stride >> s->ss_v;
+                decode_sb_mem(ctx, row + hbs, col, lflvl, yoff, uvoff, bl + 1);
+                decode_sb_mem(ctx, row + hbs, col + hbs, lflvl,
+                              yoff + 8 * hbs * bytesperpixel,
+                              uvoff + (8 * hbs * bytesperpixel >> s->ss_h), bl + 1);
+            } else {
+                yoff  += hbs * 8 * bytesperpixel;
+                uvoff += hbs * 8 * bytesperpixel >> s->ss_h;
+                decode_sb_mem(ctx, row, col + hbs, lflvl, yoff, uvoff, bl + 1);
+            }
+        } else if (row + hbs < s->rows) {
+            yoff  += hbs * 8 * y_stride;
+            uvoff += hbs * 8 * uv_stride >> s->ss_v;
+            decode_sb_mem(ctx, row + hbs, col, lflvl, yoff, uvoff, bl + 1);
+        }
+    }
+}
+
+static av_always_inline void filter_plane_cols(VP9Context *s, int col, int ss_h, int ss_v,
+                                               uint8_t *lvl, uint8_t (*mask)[4],
+                                               uint8_t *dst, ptrdiff_t ls)
+{
+    int y, x, bytesperpixel = s->bytesperpixel;
+
+    // filter edges between columns (e.g. block1 | block2)
+    for (y = 0; y < 8; y += 2 << ss_v, dst += 16 * ls, lvl += 16 << ss_v) {
+        uint8_t *ptr = dst, *l = lvl, *hmask1 = mask[y], *hmask2 = mask[y + 1 + ss_v];
+        unsigned hm1 = hmask1[0] | hmask1[1] | hmask1[2], hm13 = hmask1[3];
+        unsigned hm2 = hmask2[1] | hmask2[2], hm23 = hmask2[3];
+        unsigned hm = hm1 | hm2 | hm13 | hm23;
+
+        for (x = 1; hm & ~(x - 1); x <<= 1, ptr += 8 * bytesperpixel >> ss_h) {
+            if (col || x > 1) {
+                if (hm1 & x) {
+                    int L = *l, H = L >> 4;
+                    int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+
+                    if (hmask1[0] & x) {
+                        if (hmask2[0] & x) {
+                            av_assert2(l[8 << ss_v] == L);
+                            s->dsp.loop_filter_16[0](ptr, ls, E, I, H);
+                        } else {
+                            s->dsp.loop_filter_8[2][0](ptr, ls, E, I, H);
+                        }
+                    } else if (hm2 & x) {
+                        L = l[8 << ss_v];
+                        H |= (L >> 4) << 8;
+                        E |= s->filter.mblim_lut[L] << 8;
+                        I |= s->filter.lim_lut[L] << 8;
+                        s->dsp.loop_filter_mix2[!!(hmask1[1] & x)]
+                                               [!!(hmask2[1] & x)]
+                                               [0](ptr, ls, E, I, H);
+                    } else {
+                        s->dsp.loop_filter_8[!!(hmask1[1] & x)]
+                                            [0](ptr, ls, E, I, H);
+                    }
+                } else if (hm2 & x) {
+                    int L = l[8 << ss_v], H = L >> 4;
+                    int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+
+                    s->dsp.loop_filter_8[!!(hmask2[1] & x)]
+                                        [0](ptr + 8 * ls, ls, E, I, H);
+                }
+            }
+            if (ss_h) {
+                if (x & 0xAA)
+                    l += 2;
             } else {
-                tile_size = AV_RB32(data);
-                data     += 4;
-                size     -= 4;
+                if (hm13 & x) {
+                    int L = *l, H = L >> 4;
+                    int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+
+                    if (hm23 & x) {
+                        L = l[8 << ss_v];
+                        H |= (L >> 4) << 8;
+                        E |= s->filter.mblim_lut[L] << 8;
+                        I |= s->filter.lim_lut[L] << 8;
+                        s->dsp.loop_filter_mix2[0][0][0](ptr + 4 * bytesperpixel, ls, E, I, H);
+                    } else {
+                        s->dsp.loop_filter_8[0][0](ptr + 4 * bytesperpixel, ls, E, I, H);
+                    }
+                } else if (hm23 & x) {
+                    int L = l[8 << ss_v], H = L >> 4;
+                    int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+
+                    s->dsp.loop_filter_8[0][0](ptr + 8 * ls + 4 * bytesperpixel, ls, E, I, H);
+                }
+                l++;
             }
-            if (tile_size > size)
-                return AVERROR_INVALIDDATA;
-            ff_vp56_init_range_decoder(&s->c_b[tile_col], data, tile_size);
-            if (vp56_rac_get_prob_branchy(&s->c_b[tile_col], 128)) // marker bit
-                return AVERROR_INVALIDDATA;
-            data += tile_size;
-            size -= tile_size;
-        }
-
-        for (row = s->tiling.tile_row_start;
-             row < s->tiling.tile_row_end;
-             row += 8, yoff += s->cur_frame->linesize[0] * 64,
-             uvoff += s->cur_frame->linesize[1] * 32) {
-            VP9Filter *lflvl = s->lflvl;
-            ptrdiff_t yoff2 = yoff, uvoff2 = uvoff;
-
-            for (tile_col = 0; tile_col < s->tiling.tile_cols; tile_col++) {
-                set_tile_offset(&s->tiling.tile_col_start,
-                                &s->tiling.tile_col_end,
-                                tile_col, s->tiling.log2_tile_cols, s->sb_cols);
-
-                memset(s->left_partition_ctx, 0, 8);
-                memset(s->left_skip_ctx, 0, 8);
-                if (s->keyframe || s->intraonly)
-                    memset(s->left_mode_ctx, DC_PRED, 16);
-                else
-                    memset(s->left_mode_ctx, NEARESTMV, 8);
-                memset(s->left_y_nnz_ctx, 0, 16);
-                memset(s->left_uv_nnz_ctx, 0, 16);
-                memset(s->left_segpred_ctx, 0, 8);
-
-                memcpy(&s->c, &s->c_b[tile_col], sizeof(s->c));
-                for (col = s->tiling.tile_col_start;
-                     col < s->tiling.tile_col_end;
-                     col += 8, yoff2 += 64, uvoff2 += 32, lflvl++) {
-                    // FIXME integrate with lf code (i.e. zero after each
-                    // use, similar to invtxfm coefficients, or similar)
-                    memset(lflvl->mask, 0, sizeof(lflvl->mask));
-
-                    if ((ret = decode_subblock(avctx, row, col, lflvl,
-                                               yoff2, uvoff2, BL_64X64)) < 0)
-                        return ret;
+        }
+    }
+}
+
+static av_always_inline void filter_plane_rows(VP9Context *s, int row, int ss_h, int ss_v,
+                                               uint8_t *lvl, uint8_t (*mask)[4],
+                                               uint8_t *dst, ptrdiff_t ls)
+{
+    int y, x, bytesperpixel = s->bytesperpixel;
+
+    //                                 block1
+    // filter edges between rows (e.g. ------)
+    //                                 block2
+    for (y = 0; y < 8; y++, dst += 8 * ls >> ss_v) {
+        uint8_t *ptr = dst, *l = lvl, *vmask = mask[y];
+        unsigned vm = vmask[0] | vmask[1] | vmask[2], vm3 = vmask[3];
+
+        for (x = 1; vm & ~(x - 1); x <<= (2 << ss_h), ptr += 16 * bytesperpixel, l += 2 << ss_h) {
+            if (row || y) {
+                if (vm & x) {
+                    int L = *l, H = L >> 4;
+                    int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+
+                    if (vmask[0] & x) {
+                        if (vmask[0] & (x << (1 + ss_h))) {
+                            av_assert2(l[1 + ss_h] == L);
+                            s->dsp.loop_filter_16[1](ptr, ls, E, I, H);
+                        } else {
+                            s->dsp.loop_filter_8[2][1](ptr, ls, E, I, H);
+                        }
+                    } else if (vm & (x << (1 + ss_h))) {
+                        L = l[1 + ss_h];
+                        H |= (L >> 4) << 8;
+                        E |= s->filter.mblim_lut[L] << 8;
+                        I |= s->filter.lim_lut[L] << 8;
+                        s->dsp.loop_filter_mix2[!!(vmask[1] &  x)]
+                                               [!!(vmask[1] & (x << (1 + ss_h)))]
+                                               [1](ptr, ls, E, I, H);
+                    } else {
+                        s->dsp.loop_filter_8[!!(vmask[1] & x)]
+                                            [1](ptr, ls, E, I, H);
+                    }
+                } else if (vm & (x << (1 + ss_h))) {
+                    int L = l[1 + ss_h], H = L >> 4;
+                    int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+
+                    s->dsp.loop_filter_8[!!(vmask[1] & (x << (1 + ss_h)))]
+                                        [1](ptr + 8 * bytesperpixel, ls, E, I, H);
                 }
-                memcpy(&s->c_b[tile_col], &s->c, sizeof(s->c));
-            }
-
-            // backup pre-loopfilter reconstruction data for intra
-            // prediction of next row of sb64s
-            if (row + 8 < s->rows) {
-                memcpy(s->intra_pred_data[0],
-                       s->cur_frame->data[0] + yoff +
-                       63 * s->cur_frame->linesize[0],
-                       8 * s->cols);
-                memcpy(s->intra_pred_data[1],
-                       s->cur_frame->data[1] + uvoff +
-                       31 * s->cur_frame->linesize[1],
-                       4 * s->cols);
-                memcpy(s->intra_pred_data[2],
-                       s->cur_frame->data[2] + uvoff +
-                       31 * s->cur_frame->linesize[2],
-                       4 * s->cols);
-            }
-
-            // loopfilter one row
-            if (s->filter.level) {
-                yoff2  = yoff;
-                uvoff2 = uvoff;
-                lflvl  = s->lflvl;
-                for (col = 0; col < s->cols;
-                     col += 8, yoff2 += 64, uvoff2 += 32, lflvl++)
-                    loopfilter_subblock(avctx, lflvl, row, col, yoff2, uvoff2);
-            }
-        }
-    }
-
-    // bw adaptivity (or in case of parallel decoding mode, fw adaptivity
-    // probability maintenance between frames)
-    if (s->refreshctx) {
-        if (s->parallelmode) {
-            int j, k, l, m;
-            for (i = 0; i < 4; i++) {
-                for (j = 0; j < 2; j++)
-                    for (k = 0; k < 2; k++)
-                        for (l = 0; l < 6; l++)
-                            for (m = 0; m < 6; m++)
-                                memcpy(s->prob_ctx[s->framectxid].coef[i][j][k][l][m],
-                                       s->prob.coef[i][j][k][l][m], 3);
-                if (s->txfmmode == i)
-                    break;
-            }
-            s->prob_ctx[s->framectxid].p = s->prob.p;
+            }
+            if (!ss_v) {
+                if (vm3 & x) {
+                    int L = *l, H = L >> 4;
+                    int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+
+                    if (vm3 & (x << (1 + ss_h))) {
+                        L = l[1 + ss_h];
+                        H |= (L >> 4) << 8;
+                        E |= s->filter.mblim_lut[L] << 8;
+                        I |= s->filter.lim_lut[L] << 8;
+                        s->dsp.loop_filter_mix2[0][0][1](ptr + ls * 4, ls, E, I, H);
+                    } else {
+                        s->dsp.loop_filter_8[0][1](ptr + ls * 4, ls, E, I, H);
+                    }
+                } else if (vm3 & (x << (1 + ss_h))) {
+                    int L = l[1 + ss_h], H = L >> 4;
+                    int E = s->filter.mblim_lut[L], I = s->filter.lim_lut[L];
+
+                    s->dsp.loop_filter_8[0][1](ptr + ls * 4 + 8 * bytesperpixel, ls, E, I, H);
+                }
+            }
+        }
+        if (ss_v) {
+            if (y & 1)
+                lvl += 16;
         } else {
-            ff_vp9_adapt_probs(s);
+            lvl += 8;
         }
     }
-    FFSWAP(VP9MVRefPair *, s->mv[0], s->mv[1]);
+}
 
-    // ref frame setup
-    for (i = 0; i < 8; i++)
-        if (s->refreshrefmask & (1 << i)) {
-            av_frame_unref(s->refs[i]);
-            ret = av_frame_ref(s->refs[i], s->cur_frame);
-            if (ret < 0)
-                return ret;
+static void loopfilter_sb(AVCodecContext *ctx, struct VP9Filter *lflvl,
+                          int row, int col, ptrdiff_t yoff, ptrdiff_t uvoff)
+{
+    VP9Context *s = ctx->priv_data;
+    AVFrame *f = s->frames[CUR_FRAME].tf.f;
+    uint8_t *dst = f->data[0] + yoff;
+    ptrdiff_t ls_y = f->linesize[0], ls_uv = f->linesize[1];
+    uint8_t (*uv_masks)[8][4] = lflvl->mask[s->ss_h | s->ss_v];
+    int p;
+
+    // FIXME in how far can we interleave the v/h loopfilter calls? E.g.
+    // if you think of them as acting on a 8x8 block max, we can interleave
+    // each v/h within the single x loop, but that only works if we work on
+    // 8 pixel blocks, and we won't always do that (we want at least 16px
+    // to use SSE2 optimizations, perhaps 32 for AVX2)
+
+    filter_plane_cols(s, col, 0, 0, lflvl->level, lflvl->mask[0][0], dst, ls_y);
+    filter_plane_rows(s, row, 0, 0, lflvl->level, lflvl->mask[0][1], dst, ls_y);
+
+    for (p = 0; p < 2; p++) {
+        dst = f->data[1 + p] + uvoff;
+        filter_plane_cols(s, col, s->ss_h, s->ss_v, lflvl->level, uv_masks[0], dst, ls_uv);
+        filter_plane_rows(s, row, s->ss_h, s->ss_v, lflvl->level, uv_masks[1], dst, ls_uv);
+    }
+}
+
+static void set_tile_offset(int *start, int *end, int idx, int log2_n, int n)
+{
+    int sb_start = ( idx      * n) >> log2_n;
+    int sb_end   = ((idx + 1) * n) >> log2_n;
+    *start = FFMIN(sb_start, n) << 3;
+    *end   = FFMIN(sb_end,   n) << 3;
+}
+
+static av_always_inline void adapt_prob(uint8_t *p, unsigned ct0, unsigned ct1,
+                                        int max_count, int update_factor)
+{
+    unsigned ct = ct0 + ct1, p2, p1;
+
+    if (!ct)
+        return;
+
+    p1 = *p;
+    p2 = ((ct0 << 8) + (ct >> 1)) / ct;
+    p2 = av_clip(p2, 1, 255);
+    ct = FFMIN(ct, max_count);
+    update_factor = FASTDIV(update_factor * ct, max_count);
+
+    // (p1 * (256 - update_factor) + p2 * update_factor + 128) >> 8
+    *p = p1 + (((p2 - p1) * update_factor + 128) >> 8);
+}
+
+static void adapt_probs(VP9Context *s)
+{
+    int i, j, k, l, m;
+    prob_context *p = &s->prob_ctx[s->framectxid].p;
+    int uf = (s->keyframe || s->intraonly || !s->last_keyframe) ? 112 : 128;
+
+    // coefficients
+    for (i = 0; i < 4; i++)
+        for (j = 0; j < 2; j++)
+            for (k = 0; k < 2; k++)
+                for (l = 0; l < 6; l++)
+                    for (m = 0; m < 6; m++) {
+                        uint8_t *pp = s->prob_ctx[s->framectxid].coef[i][j][k][l][m];
+                        unsigned *e = s->counts.eob[i][j][k][l][m];
+                        unsigned *c = s->counts.coef[i][j][k][l][m];
+
+                        if (l == 0 && m >= 3) // dc only has 3 pt
+                            break;
+
+                        adapt_prob(&pp[0], e[0], e[1], 24, uf);
+                        adapt_prob(&pp[1], c[0], c[1] + c[2], 24, uf);
+                        adapt_prob(&pp[2], c[1], c[2], 24, uf);
+                    }
+
+    if (s->keyframe || s->intraonly) {
+        memcpy(p->skip,  s->prob.p.skip,  sizeof(p->skip));
+        memcpy(p->tx32p, s->prob.p.tx32p, sizeof(p->tx32p));
+        memcpy(p->tx16p, s->prob.p.tx16p, sizeof(p->tx16p));
+        memcpy(p->tx8p,  s->prob.p.tx8p,  sizeof(p->tx8p));
+        return;
+    }
+
+    // skip flag
+    for (i = 0; i < 3; i++)
+        adapt_prob(&p->skip[i], s->counts.skip[i][0], s->counts.skip[i][1], 20, 128);
+
+    // intra/inter flag
+    for (i = 0; i < 4; i++)
+        adapt_prob(&p->intra[i], s->counts.intra[i][0], s->counts.intra[i][1], 20, 128);
+
+    // comppred flag
+    if (s->comppredmode == PRED_SWITCHABLE) {
+      for (i = 0; i < 5; i++)
+          adapt_prob(&p->comp[i], s->counts.comp[i][0], s->counts.comp[i][1], 20, 128);
+    }
+
+    // reference frames
+    if (s->comppredmode != PRED_SINGLEREF) {
+      for (i = 0; i < 5; i++)
+          adapt_prob(&p->comp_ref[i], s->counts.comp_ref[i][0],
+                     s->counts.comp_ref[i][1], 20, 128);
+    }
+
+    if (s->comppredmode != PRED_COMPREF) {
+      for (i = 0; i < 5; i++) {
+          uint8_t *pp = p->single_ref[i];
+          unsigned (*c)[2] = s->counts.single_ref[i];
+
+          adapt_prob(&pp[0], c[0][0], c[0][1], 20, 128);
+          adapt_prob(&pp[1], c[1][0], c[1][1], 20, 128);
+      }
+    }
+
+    // block partitioning
+    for (i = 0; i < 4; i++)
+        for (j = 0; j < 4; j++) {
+            uint8_t *pp = p->partition[i][j];
+            unsigned *c = s->counts.partition[i][j];
+
+            adapt_prob(&pp[0], c[0], c[1] + c[2] + c[3], 20, 128);
+            adapt_prob(&pp[1], c[1], c[2] + c[3], 20, 128);
+            adapt_prob(&pp[2], c[2], c[3], 20, 128);
         }
 
-    if (s->invisible)
-        av_frame_unref(s->cur_frame);
-    else
-        *got_frame = 1;
+    // tx size
+    if (s->txfmmode == TX_SWITCHABLE) {
+      for (i = 0; i < 2; i++) {
+          unsigned *c16 = s->counts.tx16p[i], *c32 = s->counts.tx32p[i];
+
+          adapt_prob(&p->tx8p[i], s->counts.tx8p[i][0], s->counts.tx8p[i][1], 20, 128);
+          adapt_prob(&p->tx16p[i][0], c16[0], c16[1] + c16[2], 20, 128);
+          adapt_prob(&p->tx16p[i][1], c16[1], c16[2], 20, 128);
+          adapt_prob(&p->tx32p[i][0], c32[0], c32[1] + c32[2] + c32[3], 20, 128);
+          adapt_prob(&p->tx32p[i][1], c32[1], c32[2] + c32[3], 20, 128);
+          adapt_prob(&p->tx32p[i][2], c32[2], c32[3], 20, 128);
+      }
+    }
+
+    // interpolation filter
+    if (s->filtermode == FILTER_SWITCHABLE) {
+        for (i = 0; i < 4; i++) {
+            uint8_t *pp = p->filter[i];
+            unsigned *c = s->counts.filter[i];
+
+            adapt_prob(&pp[0], c[0], c[1] + c[2], 20, 128);
+            adapt_prob(&pp[1], c[1], c[2], 20, 128);
+        }
+    }
+
+    // inter modes
+    for (i = 0; i < 7; i++) {
+        uint8_t *pp = p->mv_mode[i];
+        unsigned *c = s->counts.mv_mode[i];
+
+        adapt_prob(&pp[0], c[2], c[1] + c[0] + c[3], 20, 128);
+        adapt_prob(&pp[1], c[0], c[1] + c[3], 20, 128);
+        adapt_prob(&pp[2], c[1], c[3], 20, 128);
+    }
+
+    // mv joints
+    {
+        uint8_t *pp = p->mv_joint;
+        unsigned *c = s->counts.mv_joint;
+
+        adapt_prob(&pp[0], c[0], c[1] + c[2] + c[3], 20, 128);
+        adapt_prob(&pp[1], c[1], c[2] + c[3], 20, 128);
+        adapt_prob(&pp[2], c[2], c[3], 20, 128);
+    }
+
+    // mv components
+    for (i = 0; i < 2; i++) {
+        uint8_t *pp;
+        unsigned *c, (*c2)[2], sum;
+
+        adapt_prob(&p->mv_comp[i].sign, s->counts.mv_comp[i].sign[0],
+                   s->counts.mv_comp[i].sign[1], 20, 128);
+
+        pp = p->mv_comp[i].classes;
+        c = s->counts.mv_comp[i].classes;
+        sum = c[1] + c[2] + c[3] + c[4] + c[5] + c[6] + c[7] + c[8] + c[9] + c[10];
+        adapt_prob(&pp[0], c[0], sum, 20, 128);
+        sum -= c[1];
+        adapt_prob(&pp[1], c[1], sum, 20, 128);
+        sum -= c[2] + c[3];
+        adapt_prob(&pp[2], c[2] + c[3], sum, 20, 128);
+        adapt_prob(&pp[3], c[2], c[3], 20, 128);
+        sum -= c[4] + c[5];
+        adapt_prob(&pp[4], c[4] + c[5], sum, 20, 128);
+        adapt_prob(&pp[5], c[4], c[5], 20, 128);
+        sum -= c[6];
+        adapt_prob(&pp[6], c[6], sum, 20, 128);
+        adapt_prob(&pp[7], c[7] + c[8], c[9] + c[10], 20, 128);
+        adapt_prob(&pp[8], c[7], c[8], 20, 128);
+        adapt_prob(&pp[9], c[9], c[10], 20, 128);
+
+        adapt_prob(&p->mv_comp[i].class0, s->counts.mv_comp[i].class0[0],
+                   s->counts.mv_comp[i].class0[1], 20, 128);
+        pp = p->mv_comp[i].bits;
+        c2 = s->counts.mv_comp[i].bits;
+        for (j = 0; j < 10; j++)
+            adapt_prob(&pp[j], c2[j][0], c2[j][1], 20, 128);
+
+        for (j = 0; j < 2; j++) {
+            pp = p->mv_comp[i].class0_fp[j];
+            c = s->counts.mv_comp[i].class0_fp[j];
+            adapt_prob(&pp[0], c[0], c[1] + c[2] + c[3], 20, 128);
+            adapt_prob(&pp[1], c[1], c[2] + c[3], 20, 128);
+            adapt_prob(&pp[2], c[2], c[3], 20, 128);
+        }
+        pp = p->mv_comp[i].fp;
+        c = s->counts.mv_comp[i].fp;
+        adapt_prob(&pp[0], c[0], c[1] + c[2] + c[3], 20, 128);
+        adapt_prob(&pp[1], c[1], c[2] + c[3], 20, 128);
+        adapt_prob(&pp[2], c[2], c[3], 20, 128);
+
+        if (s->highprecisionmvs) {
+            adapt_prob(&p->mv_comp[i].class0_hp, s->counts.mv_comp[i].class0_hp[0],
+                       s->counts.mv_comp[i].class0_hp[1], 20, 128);
+            adapt_prob(&p->mv_comp[i].hp, s->counts.mv_comp[i].hp[0],
+                       s->counts.mv_comp[i].hp[1], 20, 128);
+        }
+    }
+
+    // y intra modes
+    for (i = 0; i < 4; i++) {
+        uint8_t *pp = p->y_mode[i];
+        unsigned *c = s->counts.y_mode[i], sum, s2;
+
+        sum = c[0] + c[1] + c[3] + c[4] + c[5] + c[6] + c[7] + c[8] + c[9];
+        adapt_prob(&pp[0], c[DC_PRED], sum, 20, 128);
+        sum -= c[TM_VP8_PRED];
+        adapt_prob(&pp[1], c[TM_VP8_PRED], sum, 20, 128);
+        sum -= c[VERT_PRED];
+        adapt_prob(&pp[2], c[VERT_PRED], sum, 20, 128);
+        s2 = c[HOR_PRED] + c[DIAG_DOWN_RIGHT_PRED] + c[VERT_RIGHT_PRED];
+        sum -= s2;
+        adapt_prob(&pp[3], s2, sum, 20, 128);
+        s2 -= c[HOR_PRED];
+        adapt_prob(&pp[4], c[HOR_PRED], s2, 20, 128);
+        adapt_prob(&pp[5], c[DIAG_DOWN_RIGHT_PRED], c[VERT_RIGHT_PRED], 20, 128);
+        sum -= c[DIAG_DOWN_LEFT_PRED];
+        adapt_prob(&pp[6], c[DIAG_DOWN_LEFT_PRED], sum, 20, 128);
+        sum -= c[VERT_LEFT_PRED];
+        adapt_prob(&pp[7], c[VERT_LEFT_PRED], sum, 20, 128);
+        adapt_prob(&pp[8], c[HOR_DOWN_PRED], c[HOR_UP_PRED], 20, 128);
+    }
+
+    // uv intra modes
+    for (i = 0; i < 10; i++) {
+        uint8_t *pp = p->uv_mode[i];
+        unsigned *c = s->counts.uv_mode[i], sum, s2;
+
+        sum = c[0] + c[1] + c[3] + c[4] + c[5] + c[6] + c[7] + c[8] + c[9];
+        adapt_prob(&pp[0], c[DC_PRED], sum, 20, 128);
+        sum -= c[TM_VP8_PRED];
+        adapt_prob(&pp[1], c[TM_VP8_PRED], sum, 20, 128);
+        sum -= c[VERT_PRED];
+        adapt_prob(&pp[2], c[VERT_PRED], sum, 20, 128);
+        s2 = c[HOR_PRED] + c[DIAG_DOWN_RIGHT_PRED] + c[VERT_RIGHT_PRED];
+        sum -= s2;
+        adapt_prob(&pp[3], s2, sum, 20, 128);
+        s2 -= c[HOR_PRED];
+        adapt_prob(&pp[4], c[HOR_PRED], s2, 20, 128);
+        adapt_prob(&pp[5], c[DIAG_DOWN_RIGHT_PRED], c[VERT_RIGHT_PRED], 20, 128);
+        sum -= c[DIAG_DOWN_LEFT_PRED];
+        adapt_prob(&pp[6], c[DIAG_DOWN_LEFT_PRED], sum, 20, 128);
+        sum -= c[VERT_LEFT_PRED];
+        adapt_prob(&pp[7], c[VERT_LEFT_PRED], sum, 20, 128);
+        adapt_prob(&pp[8], c[HOR_DOWN_PRED], c[HOR_UP_PRED], 20, 128);
+    }
+}
+
+static void free_buffers(VP9Context *s)
+{
+    av_freep(&s->intra_pred_data[0]);
+    av_freep(&s->b_base);
+    av_freep(&s->block_base);
+}
+
+static av_cold int vp9_decode_free(AVCodecContext *ctx)
+{
+    VP9Context *s = ctx->priv_data;
+    int i;
+
+    for (i = 0; i < 3; i++) {
+        if (s->frames[i].tf.f->data[0])
+            vp9_unref_frame(ctx, &s->frames[i]);
+        av_frame_free(&s->frames[i].tf.f);
+    }
+    for (i = 0; i < 8; i++) {
+        if (s->refs[i].f->data[0])
+            ff_thread_release_buffer(ctx, &s->refs[i]);
+        av_frame_free(&s->refs[i].f);
+        if (s->next_refs[i].f->data[0])
+            ff_thread_release_buffer(ctx, &s->next_refs[i]);
+        av_frame_free(&s->next_refs[i].f);
+    }
+    free_buffers(s);
+    av_freep(&s->c_b);
+    s->c_b_size = 0;
 
     return 0;
 }
 
-static int vp9_decode_packet(AVCodecContext *avctx, void *frame,
-                             int *got_frame, AVPacket *avpkt)
+
+static int vp9_decode_frame(AVCodecContext *ctx, void *frame,
+                            int *got_frame, AVPacket *pkt)
 {
-    const uint8_t *data = avpkt->data;
-    int size            = avpkt->size;
-    int marker, ret;
-
-    /* Read superframe index - this is a collection of individual frames
-     * that together lead to one visible frame */
-    marker = data[size - 1];
-    if ((marker & 0xe0) == 0xc0) {
-        int nbytes   = 1 + ((marker >> 3) & 0x3);
-        int n_frames = 1 + (marker & 0x7);
-        int idx_sz   = 2 + n_frames * nbytes;
-
-        if (size >= idx_sz && data[size - idx_sz] == marker) {
-            const uint8_t *idx = data + size + 1 - idx_sz;
-
-            while (n_frames--) {
-                unsigned sz = AV_RL32(idx);
-
-                if (nbytes < 4)
-                    sz &= (1 << (8 * nbytes)) - 1;
-                idx += nbytes;
-
-                if (sz > size) {
-                    av_log(avctx, AV_LOG_ERROR,
-                           "Superframe packet size too big: %u > %d\n",
-                           sz, size);
-                    return AVERROR_INVALIDDATA;
+    const uint8_t *data = pkt->data;
+    int size = pkt->size;
+    VP9Context *s = ctx->priv_data;
+    int res, tile_row, tile_col, i, ref, row, col;
+    int retain_segmap_ref = s->segmentation.enabled && !s->segmentation.update_map;
+    ptrdiff_t yoff, uvoff, ls_y, ls_uv;
+    AVFrame *f;
+    int bytesperpixel;
+
+    if ((res = decode_frame_header(ctx, data, size, &ref)) < 0) {
+        return res;
+    } else if (res == 0) {
+        if (!s->refs[ref].f->data[0]) {
+            av_log(ctx, AV_LOG_ERROR, "Requested reference %d not available\n", ref);
+            return AVERROR_INVALIDDATA;
+        }
+        if ((res = av_frame_ref(frame, s->refs[ref].f)) < 0)
+            return res;
+        ((AVFrame *)frame)->pkt_pts = pkt->pts;
+        ((AVFrame *)frame)->pkt_dts = pkt->dts;
+        for (i = 0; i < 8; i++) {
+            if (s->next_refs[i].f->data[0])
+                ff_thread_release_buffer(ctx, &s->next_refs[i]);
+            if (s->refs[i].f->data[0] &&
+                (res = ff_thread_ref_frame(&s->next_refs[i], &s->refs[i])) < 0)
+                return res;
+        }
+        *got_frame = 1;
+        return pkt->size;
+    }
+    data += res;
+    size -= res;
+
+    if (!retain_segmap_ref) {
+        if (s->frames[REF_FRAME_SEGMAP].tf.f->data[0])
+            vp9_unref_frame(ctx, &s->frames[REF_FRAME_SEGMAP]);
+        if (!s->keyframe && !s->intraonly && !s->errorres && s->frames[CUR_FRAME].tf.f->data[0] &&
+            (res = vp9_ref_frame(ctx, &s->frames[REF_FRAME_SEGMAP], &s->frames[CUR_FRAME])) < 0)
+            return res;
+    }
+    if (s->frames[REF_FRAME_MVPAIR].tf.f->data[0])
+        vp9_unref_frame(ctx, &s->frames[REF_FRAME_MVPAIR]);
+    if (!s->intraonly && !s->keyframe && !s->errorres && s->frames[CUR_FRAME].tf.f->data[0] &&
+        (res = vp9_ref_frame(ctx, &s->frames[REF_FRAME_MVPAIR], &s->frames[CUR_FRAME])) < 0)
+        return res;
+    if (s->frames[CUR_FRAME].tf.f->data[0])
+        vp9_unref_frame(ctx, &s->frames[CUR_FRAME]);
+    if ((res = vp9_alloc_frame(ctx, &s->frames[CUR_FRAME])) < 0)
+        return res;
+    f = s->frames[CUR_FRAME].tf.f;
+    f->key_frame = s->keyframe;
+    f->pict_type = (s->keyframe || s->intraonly) ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
+    ls_y = f->linesize[0];
+    ls_uv =f->linesize[1];
+
+    // ref frame setup
+    for (i = 0; i < 8; i++) {
+        if (s->next_refs[i].f->data[0])
+            ff_thread_release_buffer(ctx, &s->next_refs[i]);
+        if (s->refreshrefmask & (1 << i)) {
+            res = ff_thread_ref_frame(&s->next_refs[i], &s->frames[CUR_FRAME].tf);
+        } else if (s->refs[i].f->data[0]) {
+            res = ff_thread_ref_frame(&s->next_refs[i], &s->refs[i]);
+        }
+        if (res < 0)
+            return res;
+    }
+
+    // main tile decode loop
+    bytesperpixel = s->bytesperpixel;
+    memset(s->above_partition_ctx, 0, s->cols);
+    memset(s->above_skip_ctx, 0, s->cols);
+    if (s->keyframe || s->intraonly) {
+        memset(s->above_mode_ctx, DC_PRED, s->cols * 2);
+    } else {
+        memset(s->above_mode_ctx, NEARESTMV, s->cols);
+    }
+    memset(s->above_y_nnz_ctx, 0, s->sb_cols * 16);
+    memset(s->above_uv_nnz_ctx[0], 0, s->sb_cols * 16 >> s->ss_h);
+    memset(s->above_uv_nnz_ctx[1], 0, s->sb_cols * 16 >> s->ss_h);
+    memset(s->above_segpred_ctx, 0, s->cols);
+    s->pass = s->frames[CUR_FRAME].uses_2pass =
+        ctx->active_thread_type == FF_THREAD_FRAME && s->refreshctx && !s->parallelmode;
+    if ((res = update_block_buffers(ctx)) < 0) {
+        av_log(ctx, AV_LOG_ERROR,
+               "Failed to allocate block buffers\n");
+        return res;
+    }
+    if (s->refreshctx && s->parallelmode) {
+        int j, k, l, m;
+
+        for (i = 0; i < 4; i++) {
+            for (j = 0; j < 2; j++)
+                for (k = 0; k < 2; k++)
+                    for (l = 0; l < 6; l++)
+                        for (m = 0; m < 6; m++)
+                            memcpy(s->prob_ctx[s->framectxid].coef[i][j][k][l][m],
+                                   s->prob.coef[i][j][k][l][m], 3);
+            if (s->txfmmode == i)
+                break;
+        }
+        s->prob_ctx[s->framectxid].p = s->prob.p;
+        ff_thread_finish_setup(ctx);
+    } else if (!s->refreshctx) {
+        ff_thread_finish_setup(ctx);
+    }
+
+    do {
+        yoff = uvoff = 0;
+        s->b = s->b_base;
+        s->block = s->block_base;
+        s->uvblock[0] = s->uvblock_base[0];
+        s->uvblock[1] = s->uvblock_base[1];
+        s->eob = s->eob_base;
+        s->uveob[0] = s->uveob_base[0];
+        s->uveob[1] = s->uveob_base[1];
+
+        for (tile_row = 0; tile_row < s->tiling.tile_rows; tile_row++) {
+            set_tile_offset(&s->tiling.tile_row_start, &s->tiling.tile_row_end,
+                            tile_row, s->tiling.log2_tile_rows, s->sb_rows);
+            if (s->pass != 2) {
+                for (tile_col = 0; tile_col < s->tiling.tile_cols; tile_col++) {
+                    unsigned tile_size;
+
+                    if (tile_col == s->tiling.tile_cols - 1 &&
+                        tile_row == s->tiling.tile_rows - 1) {
+                        tile_size = size;
+                    } else {
+                        tile_size = AV_RB32(data);
+                        data += 4;
+                        size -= 4;
+                    }
+                    if (tile_size > size) {
+                        ff_thread_report_progress(&s->frames[CUR_FRAME].tf, INT_MAX, 0);
+                        return AVERROR_INVALIDDATA;
+                    }
+                    ff_vp56_init_range_decoder(&s->c_b[tile_col], data, tile_size);
+                    if (vp56_rac_get_prob_branchy(&s->c_b[tile_col], 128)) { // marker bit
+                        ff_thread_report_progress(&s->frames[CUR_FRAME].tf, INT_MAX, 0);
+                        return AVERROR_INVALIDDATA;
+                    }
+                    data += tile_size;
+                    size -= tile_size;
+                }
+            }
+
+            for (row = s->tiling.tile_row_start; row < s->tiling.tile_row_end;
+                 row += 8, yoff += ls_y * 64, uvoff += ls_uv * 64 >> s->ss_v) {
+                struct VP9Filter *lflvl_ptr = s->lflvl;
+                ptrdiff_t yoff2 = yoff, uvoff2 = uvoff;
+
+                for (tile_col = 0; tile_col < s->tiling.tile_cols; tile_col++) {
+                    set_tile_offset(&s->tiling.tile_col_start, &s->tiling.tile_col_end,
+                                    tile_col, s->tiling.log2_tile_cols, s->sb_cols);
+
+                    if (s->pass != 2) {
+                        memset(s->left_partition_ctx, 0, 8);
+                        memset(s->left_skip_ctx, 0, 8);
+                        if (s->keyframe || s->intraonly) {
+                            memset(s->left_mode_ctx, DC_PRED, 16);
+                        } else {
+                            memset(s->left_mode_ctx, NEARESTMV, 8);
+                        }
+                        memset(s->left_y_nnz_ctx, 0, 16);
+                        memset(s->left_uv_nnz_ctx, 0, 32);
+                        memset(s->left_segpred_ctx, 0, 8);
+
+                        memcpy(&s->c, &s->c_b[tile_col], sizeof(s->c));
+                    }
+
+                    for (col = s->tiling.tile_col_start;
+                         col < s->tiling.tile_col_end;
+                         col += 8, yoff2 += 64 * bytesperpixel,
+                         uvoff2 += 64 * bytesperpixel >> s->ss_h, lflvl_ptr++) {
+                        // FIXME integrate with lf code (i.e. zero after each
+                        // use, similar to invtxfm coefficients, or similar)
+                        if (s->pass != 1) {
+                            memset(lflvl_ptr->mask, 0, sizeof(lflvl_ptr->mask));
+                        }
+
+                        if (s->pass == 2) {
+                            decode_sb_mem(ctx, row, col, lflvl_ptr,
+                                          yoff2, uvoff2, BL_64X64);
+                        } else {
+                            decode_sb(ctx, row, col, lflvl_ptr,
+                                      yoff2, uvoff2, BL_64X64);
+                        }
+                    }
+                    if (s->pass != 2) {
+                        memcpy(&s->c_b[tile_col], &s->c, sizeof(s->c));
+                    }
+                }
+
+                if (s->pass == 1) {
+                    continue;
+                }
+
+                // backup pre-loopfilter reconstruction data for intra
+                // prediction of next row of sb64s
+                if (row + 8 < s->rows) {
+                    memcpy(s->intra_pred_data[0],
+                           f->data[0] + yoff + 63 * ls_y,
+                           8 * s->cols * bytesperpixel);
+                    memcpy(s->intra_pred_data[1],
+                           f->data[1] + uvoff + ((64 >> s->ss_v) - 1) * ls_uv,
+                           8 * s->cols * bytesperpixel >> s->ss_h);
+                    memcpy(s->intra_pred_data[2],
+                           f->data[2] + uvoff + ((64 >> s->ss_v) - 1) * ls_uv,
+                           8 * s->cols * bytesperpixel >> s->ss_h);
+                }
+
+                // loopfilter one row
+                if (s->filter.level) {
+                    yoff2 = yoff;
+                    uvoff2 = uvoff;
+                    lflvl_ptr = s->lflvl;
+                    for (col = 0; col < s->cols;
+                         col += 8, yoff2 += 64 * bytesperpixel,
+                         uvoff2 += 64 * bytesperpixel >> s->ss_h, lflvl_ptr++) {
+                        loopfilter_sb(ctx, lflvl_ptr, row, col, yoff2, uvoff2);
+                    }
                 }
 
-                ret = vp9_decode_frame(avctx, frame, got_frame, data, sz);
-                if (ret < 0)
-                    return ret;
-                data += sz;
-                size -= sz;
+                // FIXME maybe we can make this more finegrained by running the
+                // loopfilter per-block instead of after each sbrow
+                // In fact that would also make intra pred left preparation easier?
+                ff_thread_report_progress(&s->frames[CUR_FRAME].tf, row >> 3, 0);
             }
-            return size;
         }
+
+        if (s->pass < 2 && s->refreshctx && !s->parallelmode) {
+            adapt_probs(s);
+            ff_thread_finish_setup(ctx);
+        }
+    } while (s->pass++ == 1);
+    ff_thread_report_progress(&s->frames[CUR_FRAME].tf, INT_MAX, 0);
+
+    // ref frame setup
+    for (i = 0; i < 8; i++) {
+        if (s->refs[i].f->data[0])
+            ff_thread_release_buffer(ctx, &s->refs[i]);
+        ff_thread_ref_frame(&s->refs[i], &s->next_refs[i]);
     }
 
-    /* If we get here, there was no valid superframe index, i.e. this is just
-     * one whole single frame. Decode it as such from the complete input buf. */
-    if ((ret = vp9_decode_frame(avctx, frame, got_frame, data, size)) < 0)
-        return ret;
-    return size;
+    if (!s->invisible) {
+        if ((res = av_frame_ref(frame, s->frames[CUR_FRAME].tf.f)) < 0)
+            return res;
+        *got_frame = 1;
+    }
+
+    return pkt->size;
 }
 
-static av_cold int vp9_decode_free(AVCodecContext *avctx)
+static void vp9_decode_flush(AVCodecContext *ctx)
 {
-    VP9Context *s = avctx->priv_data;
+    VP9Context *s = ctx->priv_data;
     int i;
 
-    for (i = 0; i < FF_ARRAY_ELEMS(s->refs); i++)
-        av_frame_free(&s->refs[i]);
+    for (i = 0; i < 3; i++)
+        vp9_unref_frame(ctx, &s->frames[i]);
+    for (i = 0; i < 8; i++)
+        ff_thread_release_buffer(ctx, &s->refs[i]);
+}
 
-    av_freep(&s->c_b);
-    av_freep(&s->above_partition_ctx);
+static int init_frames(AVCodecContext *ctx)
+{
+    VP9Context *s = ctx->priv_data;
+    int i;
+
+    for (i = 0; i < 3; i++) {
+        s->frames[i].tf.f = av_frame_alloc();
+        if (!s->frames[i].tf.f) {
+            vp9_decode_free(ctx);
+            av_log(ctx, AV_LOG_ERROR, "Failed to allocate frame buffer %d\n", i);
+            return AVERROR(ENOMEM);
+        }
+    }
+    for (i = 0; i < 8; i++) {
+        s->refs[i].f = av_frame_alloc();
+        s->next_refs[i].f = av_frame_alloc();
+        if (!s->refs[i].f || !s->next_refs[i].f) {
+            vp9_decode_free(ctx);
+            av_log(ctx, AV_LOG_ERROR, "Failed to allocate frame buffer %d\n", i);
+            return AVERROR(ENOMEM);
+        }
+    }
 
     return 0;
 }
 
-static av_cold int vp9_decode_init(AVCodecContext *avctx)
+static av_cold int vp9_decode_init(AVCodecContext *ctx)
 {
-    VP9Context *s = avctx->priv_data;
-    int i;
+    VP9Context *s = ctx->priv_data;
 
-    avctx->pix_fmt = AV_PIX_FMT_YUV420P;
+    ctx->internal->allocate_progress = 1;
+    s->last_bpp = 0;
+    s->filter.sharpness = -1;
 
-    ff_vp9dsp_init(&s->dsp);
-    ff_videodsp_init(&s->vdsp, 8);
+    return init_frames(ctx);
+}
 
-    for (i = 0; i < FF_ARRAY_ELEMS(s->refs); i++) {
-        s->refs[i] = av_frame_alloc();
-        if (!s->refs[i]) {
-            vp9_decode_free(avctx);
-            return AVERROR(ENOMEM);
+static av_cold int vp9_decode_init_thread_copy(AVCodecContext *avctx)
+{
+    return init_frames(avctx);
+}
+
+static int vp9_decode_update_thread_context(AVCodecContext *dst, const AVCodecContext *src)
+{
+    int i, res;
+    VP9Context *s = dst->priv_data, *ssrc = src->priv_data;
+
+    // detect size changes in other threads
+    if (s->intra_pred_data[0] &&
+        (!ssrc->intra_pred_data[0] || s->cols != ssrc->cols || s->rows != ssrc->rows)) {
+        free_buffers(s);
+    }
+
+    for (i = 0; i < 3; i++) {
+        if (s->frames[i].tf.f->data[0])
+            vp9_unref_frame(dst, &s->frames[i]);
+        if (ssrc->frames[i].tf.f->data[0]) {
+            if ((res = vp9_ref_frame(dst, &s->frames[i], &ssrc->frames[i])) < 0)
+                return res;
+        }
+    }
+    for (i = 0; i < 8; i++) {
+        if (s->refs[i].f->data[0])
+            ff_thread_release_buffer(dst, &s->refs[i]);
+        if (ssrc->next_refs[i].f->data[0]) {
+            if ((res = ff_thread_ref_frame(&s->refs[i], &ssrc->next_refs[i])) < 0)
+                return res;
         }
     }
 
-    s->filter.sharpness = -1;
+    s->invisible = ssrc->invisible;
+    s->keyframe = ssrc->keyframe;
+    s->ss_v = ssrc->ss_v;
+    s->ss_h = ssrc->ss_h;
+    s->segmentation.enabled = ssrc->segmentation.enabled;
+    s->segmentation.update_map = ssrc->segmentation.update_map;
+    s->bytesperpixel = ssrc->bytesperpixel;
+    s->bpp = ssrc->bpp;
+    s->bpp_index = ssrc->bpp_index;
+    memcpy(&s->prob_ctx, &ssrc->prob_ctx, sizeof(s->prob_ctx));
+    memcpy(&s->lf_delta, &ssrc->lf_delta, sizeof(s->lf_delta));
+    if (ssrc->segmentation.enabled) {
+        memcpy(&s->segmentation.feat, &ssrc->segmentation.feat,
+               sizeof(s->segmentation.feat));
+    }
 
     return 0;
 }
 
+static const AVProfile profiles[] = {
+    { FF_PROFILE_VP9_0, "Profile 0" },
+    { FF_PROFILE_VP9_1, "Profile 1" },
+    { FF_PROFILE_VP9_2, "Profile 2" },
+    { FF_PROFILE_VP9_3, "Profile 3" },
+    { FF_PROFILE_UNKNOWN },
+};
+
 AVCodec ff_vp9_decoder = {
-    .name           = "vp9",
-    .long_name      = NULL_IF_CONFIG_SMALL("Google VP9"),
-    .type           = AVMEDIA_TYPE_VIDEO,
-    .id             = AV_CODEC_ID_VP9,
-    .priv_data_size = sizeof(VP9Context),
-    .init           = vp9_decode_init,
-    .decode         = vp9_decode_packet,
-    .flush          = vp9_decode_flush,
-    .close          = vp9_decode_free,
-    .capabilities   = CODEC_CAP_DR1,
+    .name                  = "vp9",
+    .long_name             = NULL_IF_CONFIG_SMALL("Google VP9"),
+    .type                  = AVMEDIA_TYPE_VIDEO,
+    .id                    = AV_CODEC_ID_VP9,
+    .priv_data_size        = sizeof(VP9Context),
+    .init                  = vp9_decode_init,
+    .close                 = vp9_decode_free,
+    .decode                = vp9_decode_frame,
+    .capabilities          = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
+    .flush                 = vp9_decode_flush,
+    .init_thread_copy      = ONLY_IF_THREADS_ENABLED(vp9_decode_init_thread_copy),
+    .update_thread_context = ONLY_IF_THREADS_ENABLED(vp9_decode_update_thread_context),
+    .profiles              = NULL_IF_CONFIG_SMALL(profiles),
 };