git.sesse.net Git - ffmpeg/blob - libavcodec/vaapi_h264.c

   1 /*
   2  * H.264 HW decode acceleration through VA API
   3  *
   4  * Copyright (C) 2008-2009 Splitted-Desktop Systems
   5  *
   6  * This file is part of FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include "vaapi_internal.h"
  24 #include "h264.h"
  25 #include "mpegutils.h"
  26
  27 /**
  28  * @file
  29  * This file implements the glue code between FFmpeg's and VA API's
  30  * structures for H.264 decoding.
  31  */
  32
  33 /**
  34  * Initialize an empty VA API picture.
  35  *
  36  * VA API requires a fixed-size reference picture array.
  37  */
  38 static void init_vaapi_pic(VAPictureH264 *va_pic)
  39 {
  40     va_pic->picture_id          = VA_INVALID_ID;
  41     va_pic->flags               = VA_PICTURE_H264_INVALID;
  42     va_pic->TopFieldOrderCnt    = 0;
  43     va_pic->BottomFieldOrderCnt = 0;
  44 }
  45
  46 /**
  47  * Translate an FFmpeg Picture into its VA API form.
  48  *
  49  * @param[out] va_pic          A pointer to VA API's own picture struct
  50  * @param[in]  pic             A pointer to the FFmpeg picture struct to convert
  51  * @param[in]  pic_structure   The picture field type (as defined in mpegvideo.h),
  52  *                             supersedes pic's field type if nonzero.
  53  */
  54 static void fill_vaapi_pic(VAPictureH264 *va_pic,
  55                            H264Picture   *pic,
  56                            int            pic_structure)
  57 {
  58     if (pic_structure == 0)
  59         pic_structure = pic->reference;
  60     pic_structure &= PICT_FRAME; /* PICT_TOP_FIELD|PICT_BOTTOM_FIELD */
  61
  62     va_pic->picture_id = ff_vaapi_get_surface_id(pic->f);
  63     va_pic->frame_idx  = pic->long_ref ? pic->pic_id : pic->frame_num;
  64
  65     va_pic->flags      = 0;
  66     if (pic_structure != PICT_FRAME)
  67         va_pic->flags |= (pic_structure & PICT_TOP_FIELD) ? VA_PICTURE_H264_TOP_FIELD : VA_PICTURE_H264_BOTTOM_FIELD;
  68     if (pic->reference)
  69         va_pic->flags |= pic->long_ref ? VA_PICTURE_H264_LONG_TERM_REFERENCE : VA_PICTURE_H264_SHORT_TERM_REFERENCE;
  70
  71     va_pic->TopFieldOrderCnt = 0;
  72     if (pic->field_poc[0] != INT_MAX)
  73         va_pic->TopFieldOrderCnt = pic->field_poc[0];
  74
  75     va_pic->BottomFieldOrderCnt = 0;
  76     if (pic->field_poc[1] != INT_MAX)
  77         va_pic->BottomFieldOrderCnt = pic->field_poc[1];
  78 }
  79
  80 /** Decoded Picture Buffer (DPB). */
  81 typedef struct DPB {
  82     int            size;        ///< Current number of reference frames in the DPB
  83     int            max_size;    ///< Max number of reference frames. This is FF_ARRAY_ELEMS(VAPictureParameterBufferH264.ReferenceFrames)
  84     VAPictureH264 *va_pics;     ///< Pointer to VAPictureParameterBufferH264.ReferenceFrames array
  85 } DPB;
  86
  87 /**
  88  * Append picture to the decoded picture buffer, in a VA API form that
  89  * merges the second field picture attributes with the first, if
  90  * available.  The decoded picture buffer's size must be large enough
  91  * to receive the new VA API picture object.
  92  */
  93 static int dpb_add(DPB *dpb, H264Picture *pic)
  94 {
  95     int i;
  96
  97     if (dpb->size >= dpb->max_size)
  98         return -1;
  99
 100     for (i = 0; i < dpb->size; i++) {
 101         VAPictureH264 * const va_pic = &dpb->va_pics[i];
 102         if (va_pic->picture_id == ff_vaapi_get_surface_id(pic->f)) {
 103             VAPictureH264 temp_va_pic;
 104             fill_vaapi_pic(&temp_va_pic, pic, 0);
 105
 106             if ((temp_va_pic.flags ^ va_pic->flags) & (VA_PICTURE_H264_TOP_FIELD | VA_PICTURE_H264_BOTTOM_FIELD)) {
 107                 va_pic->flags |= temp_va_pic.flags & (VA_PICTURE_H264_TOP_FIELD | VA_PICTURE_H264_BOTTOM_FIELD);
 108                 /* Merge second field */
 109                 if (temp_va_pic.flags & VA_PICTURE_H264_TOP_FIELD) {
 110                     va_pic->TopFieldOrderCnt    = temp_va_pic.TopFieldOrderCnt;
 111                 } else {
 112                     va_pic->BottomFieldOrderCnt = temp_va_pic.BottomFieldOrderCnt;
 113                 }
 114             }
 115             return 0;
 116         }
 117     }
 118
 119     fill_vaapi_pic(&dpb->va_pics[dpb->size++], pic, 0);
 120     return 0;
 121 }
 122
 123 /** Fill in VA API reference frames array. */
 124 static int fill_vaapi_ReferenceFrames(VAPictureParameterBufferH264 *pic_param,
 125                                       H264Context                  *h)
 126 {
 127     DPB dpb;
 128     int i;
 129
 130     dpb.size     = 0;
 131     dpb.max_size = FF_ARRAY_ELEMS(pic_param->ReferenceFrames);
 132     dpb.va_pics  = pic_param->ReferenceFrames;
 133     for (i = 0; i < dpb.max_size; i++)
 134         init_vaapi_pic(&dpb.va_pics[i]);
 135
 136     for (i = 0; i < h->short_ref_count; i++) {
 137         H264Picture * const pic = h->short_ref[i];
 138         if (pic && pic->reference && dpb_add(&dpb, pic) < 0)
 139             return -1;
 140     }
 141
 142     for (i = 0; i < 16; i++) {
 143         H264Picture * const pic = h->long_ref[i];
 144         if (pic && pic->reference && dpb_add(&dpb, pic) < 0)
 145             return -1;
 146     }
 147     return 0;
 148 }
 149
 150 /**
 151  * Fill in VA API reference picture lists from the FFmpeg reference
 152  * picture list.
 153  *
 154  * @param[out] RefPicList  VA API internal reference picture list
 155  * @param[in]  ref_list    A pointer to the FFmpeg reference list
 156  * @param[in]  ref_count   The number of reference pictures in ref_list
 157  */
 158 static void fill_vaapi_RefPicList(VAPictureH264 RefPicList[32],
 159                                   H264Ref  *ref_list,
 160                                   unsigned int  ref_count)
 161 {
 162     unsigned int i, n = 0;
 163     for (i = 0; i < ref_count; i++)
 164         if (ref_list[i].reference)
 165             fill_vaapi_pic(&RefPicList[n++], ref_list[i].parent,
 166                            ref_list[i].reference);
 167
 168     for (; n < 32; n++)
 169         init_vaapi_pic(&RefPicList[n]);
 170 }
 171
 172 /**
 173  * Fill in prediction weight table.
 174  *
 175  * VA API requires a plain prediction weight table as it does not infer
 176  * any value.
 177  *
 178  * @param[in]  h                   A pointer to the current H.264 context
 179  * @param[in]  list                The reference frame list index to use
 180  * @param[out] luma_weight_flag    VA API plain luma weight flag
 181  * @param[out] luma_weight         VA API plain luma weight table
 182  * @param[out] luma_offset         VA API plain luma offset table
 183  * @param[out] chroma_weight_flag  VA API plain chroma weight flag
 184  * @param[out] chroma_weight       VA API plain chroma weight table
 185  * @param[out] chroma_offset       VA API plain chroma offset table
 186  */
 187 static void fill_vaapi_plain_pred_weight_table(H264Context   *h,
 188                                                int            list,
 189                                                unsigned char *luma_weight_flag,
 190                                                short          luma_weight[32],
 191                                                short          luma_offset[32],
 192                                                unsigned char *chroma_weight_flag,
 193                                                short          chroma_weight[32][2],
 194                                                short          chroma_offset[32][2])
 195 {
 196     H264SliceContext *sl = &h->slice_ctx[0];
 197     unsigned int i, j;
 198
 199     *luma_weight_flag    = sl->luma_weight_flag[list];
 200     *chroma_weight_flag  = sl->chroma_weight_flag[list];
 201
 202     for (i = 0; i < sl->ref_count[list]; i++) {
 203         /* VA API also wants the inferred (default) values, not
 204            only what is available in the bitstream (7.4.3.2). */
 205         if (sl->luma_weight_flag[list]) {
 206             luma_weight[i] = sl->luma_weight[i][list][0];
 207             luma_offset[i] = sl->luma_weight[i][list][1];
 208         } else {
 209             luma_weight[i] = 1 << sl->luma_log2_weight_denom;
 210             luma_offset[i] = 0;
 211         }
 212         for (j = 0; j < 2; j++) {
 213             if (sl->chroma_weight_flag[list]) {
 214                 chroma_weight[i][j] = sl->chroma_weight[i][list][j][0];
 215                 chroma_offset[i][j] = sl->chroma_weight[i][list][j][1];
 216             } else {
 217                 chroma_weight[i][j] = 1 << sl->chroma_log2_weight_denom;
 218                 chroma_offset[i][j] = 0;
 219             }
 220         }
 221     }
 222 }
 223
 224 /** Initialize and start decoding a frame with VA API. */
 225 static int vaapi_h264_start_frame(AVCodecContext          *avctx,
 226                                   av_unused const uint8_t *buffer,
 227                                   av_unused uint32_t       size)
 228 {
 229     H264Context * const h = avctx->priv_data;
 230     struct vaapi_context * const vactx = avctx->hwaccel_context;
 231     VAPictureParameterBufferH264 *pic_param;
 232     VAIQMatrixBufferH264 *iq_matrix;
 233
 234     ff_dlog(avctx, "vaapi_h264_start_frame()\n");
 235
 236     vactx->slice_param_size = sizeof(VASliceParameterBufferH264);
 237
 238     /* Fill in VAPictureParameterBufferH264. */
 239     pic_param = ff_vaapi_alloc_pic_param(vactx, sizeof(VAPictureParameterBufferH264));
 240     if (!pic_param)
 241         return -1;
 242     fill_vaapi_pic(&pic_param->CurrPic, h->cur_pic_ptr, h->picture_structure);
 243     if (fill_vaapi_ReferenceFrames(pic_param, h) < 0)
 244         return -1;
 245     pic_param->picture_width_in_mbs_minus1                      = h->mb_width - 1;
 246     pic_param->picture_height_in_mbs_minus1                     = h->mb_height - 1;
 247     pic_param->bit_depth_luma_minus8                            = h->sps.bit_depth_luma - 8;
 248     pic_param->bit_depth_chroma_minus8                          = h->sps.bit_depth_chroma - 8;
 249     pic_param->num_ref_frames                                   = h->sps.ref_frame_count;
 250     pic_param->seq_fields.value                                 = 0; /* reset all bits */
 251     pic_param->seq_fields.bits.chroma_format_idc                = h->sps.chroma_format_idc;
 252     pic_param->seq_fields.bits.residual_colour_transform_flag   = h->sps.residual_color_transform_flag; /* XXX: only for 4:4:4 high profile? */
 253     pic_param->seq_fields.bits.gaps_in_frame_num_value_allowed_flag = h->sps.gaps_in_frame_num_allowed_flag;
 254     pic_param->seq_fields.bits.frame_mbs_only_flag              = h->sps.frame_mbs_only_flag;
 255     pic_param->seq_fields.bits.mb_adaptive_frame_field_flag     = h->sps.mb_aff;
 256     pic_param->seq_fields.bits.direct_8x8_inference_flag        = h->sps.direct_8x8_inference_flag;
 257     pic_param->seq_fields.bits.MinLumaBiPredSize8x8             = h->sps.level_idc >= 31; /* A.3.3.2 */
 258     pic_param->seq_fields.bits.log2_max_frame_num_minus4        = h->sps.log2_max_frame_num - 4;
 259     pic_param->seq_fields.bits.pic_order_cnt_type               = h->sps.poc_type;
 260     pic_param->seq_fields.bits.log2_max_pic_order_cnt_lsb_minus4 = h->sps.log2_max_poc_lsb - 4;
 261     pic_param->seq_fields.bits.delta_pic_order_always_zero_flag = h->sps.delta_pic_order_always_zero_flag;
 262     pic_param->num_slice_groups_minus1                          = h->pps.slice_group_count - 1;
 263     pic_param->slice_group_map_type                             = h->pps.mb_slice_group_map_type;
 264     pic_param->slice_group_change_rate_minus1                   = 0; /* XXX: unimplemented in FFmpeg */
 265     pic_param->pic_init_qp_minus26                              = h->pps.init_qp - 26;
 266     pic_param->pic_init_qs_minus26                              = h->pps.init_qs - 26;
 267     pic_param->chroma_qp_index_offset                           = h->pps.chroma_qp_index_offset[0];
 268     pic_param->second_chroma_qp_index_offset                    = h->pps.chroma_qp_index_offset[1];
 269     pic_param->pic_fields.value                                 = 0; /* reset all bits */
 270     pic_param->pic_fields.bits.entropy_coding_mode_flag         = h->pps.cabac;
 271     pic_param->pic_fields.bits.weighted_pred_flag               = h->pps.weighted_pred;
 272     pic_param->pic_fields.bits.weighted_bipred_idc              = h->pps.weighted_bipred_idc;
 273     pic_param->pic_fields.bits.transform_8x8_mode_flag          = h->pps.transform_8x8_mode;
 274     pic_param->pic_fields.bits.field_pic_flag                   = h->picture_structure != PICT_FRAME;
 275     pic_param->pic_fields.bits.constrained_intra_pred_flag      = h->pps.constrained_intra_pred;
 276     pic_param->pic_fields.bits.pic_order_present_flag           = h->pps.pic_order_present;
 277     pic_param->pic_fields.bits.deblocking_filter_control_present_flag = h->pps.deblocking_filter_parameters_present;
 278     pic_param->pic_fields.bits.redundant_pic_cnt_present_flag   = h->pps.redundant_pic_cnt_present;
 279     pic_param->pic_fields.bits.reference_pic_flag               = h->nal_ref_idc != 0;
 280     pic_param->frame_num                                        = h->frame_num;
 281
 282     /* Fill in VAIQMatrixBufferH264. */
 283     iq_matrix = ff_vaapi_alloc_iq_matrix(vactx, sizeof(VAIQMatrixBufferH264));
 284     if (!iq_matrix)
 285         return -1;
 286     memcpy(iq_matrix->ScalingList4x4, h->pps.scaling_matrix4, sizeof(iq_matrix->ScalingList4x4));
 287     memcpy(iq_matrix->ScalingList8x8[0], h->pps.scaling_matrix8[0], sizeof(iq_matrix->ScalingList8x8[0]));
 288     memcpy(iq_matrix->ScalingList8x8[1], h->pps.scaling_matrix8[3], sizeof(iq_matrix->ScalingList8x8[0]));
 289     return 0;
 290 }
 291
 292 /** End a hardware decoding based frame. */
 293 static int vaapi_h264_end_frame(AVCodecContext *avctx)
 294 {
 295     struct vaapi_context * const vactx = avctx->hwaccel_context;
 296     H264Context * const h = avctx->priv_data;
 297     H264SliceContext *sl = &h->slice_ctx[0];
 298     int ret;
 299
 300     ff_dlog(avctx, "vaapi_h264_end_frame()\n");
 301     ret = ff_vaapi_commit_slices(vactx);
 302     if (ret < 0)
 303         goto finish;
 304
 305     ret = ff_vaapi_render_picture(vactx, ff_vaapi_get_surface_id(h->cur_pic_ptr->f));
 306     if (ret < 0)
 307         goto finish;
 308
 309     ff_h264_draw_horiz_band(h, sl, 0, h->avctx->height);
 310
 311 finish:
 312     ff_vaapi_common_end_frame(avctx);
 313     return ret;
 314 }
 315
 316 /** Decode the given H.264 slice with VA API. */
 317 static int vaapi_h264_decode_slice(AVCodecContext *avctx,
 318                                    const uint8_t  *buffer,
 319                                    uint32_t        size)
 320 {
 321     H264Context * const h = avctx->priv_data;
 322     H264SliceContext *sl  = &h->slice_ctx[0];
 323     VASliceParameterBufferH264 *slice_param;
 324
 325     ff_dlog(avctx, "vaapi_h264_decode_slice(): buffer %p, size %d\n",
 326             buffer, size);
 327
 328     /* Fill in VASliceParameterBufferH264. */
 329     slice_param = (VASliceParameterBufferH264 *)ff_vaapi_alloc_slice(avctx->hwaccel_context, buffer, size);
 330     if (!slice_param)
 331         return -1;
 332     slice_param->slice_data_bit_offset          = get_bits_count(&sl->gb) + 8; /* bit buffer started beyond nal_unit_type */
 333     slice_param->first_mb_in_slice              = (sl->mb_y >> FIELD_OR_MBAFF_PICTURE(h)) * h->mb_width + sl->mb_x;
 334     slice_param->slice_type                     = ff_h264_get_slice_type(sl);
 335     slice_param->direct_spatial_mv_pred_flag    = sl->slice_type == AV_PICTURE_TYPE_B ? sl->direct_spatial_mv_pred : 0;
 336     slice_param->num_ref_idx_l0_active_minus1   = sl->list_count > 0 ? sl->ref_count[0] - 1 : 0;
 337     slice_param->num_ref_idx_l1_active_minus1   = sl->list_count > 1 ? sl->ref_count[1] - 1 : 0;
 338     slice_param->cabac_init_idc                 = sl->cabac_init_idc;
 339     slice_param->slice_qp_delta                 = sl->qscale - h->pps.init_qp;
 340     slice_param->disable_deblocking_filter_idc  = sl->deblocking_filter < 2 ? !sl->deblocking_filter : sl->deblocking_filter;
 341     slice_param->slice_alpha_c0_offset_div2     = sl->slice_alpha_c0_offset / 2;
 342     slice_param->slice_beta_offset_div2         = sl->slice_beta_offset     / 2;
 343     slice_param->luma_log2_weight_denom         = sl->luma_log2_weight_denom;
 344     slice_param->chroma_log2_weight_denom       = sl->chroma_log2_weight_denom;
 345
 346     fill_vaapi_RefPicList(slice_param->RefPicList0, sl->ref_list[0], sl->list_count > 0 ? sl->ref_count[0] : 0);
 347     fill_vaapi_RefPicList(slice_param->RefPicList1, sl->ref_list[1], sl->list_count > 1 ? sl->ref_count[1] : 0);
 348
 349     fill_vaapi_plain_pred_weight_table(h, 0,
 350                                        &slice_param->luma_weight_l0_flag,   slice_param->luma_weight_l0,   slice_param->luma_offset_l0,
 351                                        &slice_param->chroma_weight_l0_flag, slice_param->chroma_weight_l0, slice_param->chroma_offset_l0);
 352     fill_vaapi_plain_pred_weight_table(h, 1,
 353                                        &slice_param->luma_weight_l1_flag,   slice_param->luma_weight_l1,   slice_param->luma_offset_l1,
 354                                        &slice_param->chroma_weight_l1_flag, slice_param->chroma_weight_l1, slice_param->chroma_offset_l1);
 355     return 0;
 356 }
 357
 358 AVHWAccel ff_h264_vaapi_hwaccel = {
 359     .name           = "h264_vaapi",
 360     .type           = AVMEDIA_TYPE_VIDEO,
 361     .id             = AV_CODEC_ID_H264,
 362     .pix_fmt        = AV_PIX_FMT_VAAPI,
 363     .start_frame    = vaapi_h264_start_frame,
 364     .end_frame      = vaapi_h264_end_frame,
 365     .decode_slice   = vaapi_h264_decode_slice,
 366 };