X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fwnv1.c;h=5d6c91d2d29f753cb337b7aa92d97a7ed8472dd0;hb=a247ac640df3da573cd661065bf53f37863e2b46;hp=915e9c7dc9e214e064d7ede88834f1382e65dca5;hpb=0a319bcce5714f7183b0537892f7d37d7a31493a;p=ffmpeg

diff --git a/libavcodec/wnv1.c b/libavcodec/wnv1.c
index 915e9c7dc9e..5d6c91d2d29 100644
--- a/libavcodec/wnv1.c
+++ b/libavcodec/wnv1.c
@@ -24,89 +24,72 @@
  * Winnov WNV1 codec.
  */
 
+#include "libavutil/thread.h"
+
+#define BITSTREAM_READER_LE
 #include "avcodec.h"
 #include "get_bits.h"
 #include "internal.h"
-#include "mathops.h"
-
-
-typedef struct WNV1Context {
-    int shift;
-    GetBitContext gb;
-} WNV1Context;
 
-static const uint16_t code_tab[16][2] = {
-    { 0x1FD, 9 }, { 0xFD, 8 }, { 0x7D, 7 }, { 0x3D, 6 }, { 0x1D, 5 }, { 0x0D, 4 }, { 0x005, 3 },
-    { 0x000, 1 },
-    { 0x004, 3 }, { 0x0C, 4 }, { 0x1C, 5 }, { 0x3C, 6 }, { 0x7C, 7 }, { 0xFC, 8 }, { 0x1FC, 9 }, { 0xFF, 8 }
+static const uint8_t code_tab[16][2] = {
+    {  7, 1 }, {  8, 3 }, {  6, 3 }, { 9, 4 }, {  5, 4 }, { 10, 5 }, {  4, 5 },
+    { 11, 6 }, {  3, 6 }, { 12, 7 }, { 2, 7 }, { 13, 8 }, {  1, 8 }, { 14, 9 },
+    {  0, 9 }, { 15, 8 }
 };
 
 #define CODE_VLC_BITS 9
 static VLC code_vlc;
 
 /* returns modified base_value */
-static inline int wnv1_get_code(WNV1Context *w, int base_value)
+static inline int wnv1_get_code(GetBitContext *gb, int shift, int base_value)
 {
-    int v = get_vlc2(&w->gb, code_vlc.table, CODE_VLC_BITS, 1);
+    int v = get_vlc2(gb, code_vlc.table, CODE_VLC_BITS, 1);
 
-    if (v == 15)
-        return ff_reverse[get_bits(&w->gb, 8 - w->shift)];
+    if (v == 8)
+        return get_bits(gb, 8 - shift) << shift;
     else
-        return base_value + ((v - 7U) << w->shift);
+        return base_value + v * (1 << shift);
 }
 
 static int decode_frame(AVCodecContext *avctx,
                         void *data, int *got_frame,
                         AVPacket *avpkt)
 {
-    WNV1Context * const l = avctx->priv_data;
     const uint8_t *buf    = avpkt->data;
     int buf_size          = avpkt->size;
     AVFrame * const p     = data;
+    GetBitContext gb;
     unsigned char *Y,*U,*V;
-    int i, j, ret;
+    int i, j, ret, shift;
     int prev_y = 0, prev_u = 0, prev_v = 0;
-    uint8_t *rbuf;
 
     if (buf_size < 8 + avctx->height * (avctx->width/2)/8) {
         av_log(avctx, AV_LOG_ERROR, "Packet size %d is too small\n", buf_size);
         return AVERROR_INVALIDDATA;
     }
 
-    rbuf = av_malloc(buf_size + AV_INPUT_BUFFER_PADDING_SIZE);
-    if (!rbuf) {
-        av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer\n");
-        return AVERROR(ENOMEM);
-    }
-    memset(rbuf + buf_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
-
-    if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
-        av_free(rbuf);
+    if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
         return ret;
-    }
     p->key_frame = 1;
 
-    for (i = 8; i < buf_size; i++)
-        rbuf[i] = ff_reverse[buf[i]];
-
-    if ((ret = init_get_bits8(&l->gb, rbuf + 8, buf_size - 8)) < 0)
+    if ((ret = init_get_bits8(&gb, buf + 8, buf_size - 8)) < 0)
         return ret;
 
     if (buf[2] >> 4 == 6)
-        l->shift = 2;
+        shift = 2;
     else {
-        l->shift = 8 - (buf[2] >> 4);
-        if (l->shift > 4) {
+        shift = 8 - (buf[2] >> 4);
+        if (shift > 4) {
             avpriv_request_sample(avctx,
                                   "Unknown WNV1 frame header value %i",
                                   buf[2] >> 4);
-            l->shift = 4;
+            shift = 4;
         }
-        if (l->shift < 1) {
+        if (shift < 1) {
             avpriv_request_sample(avctx,
                                   "Unknown WNV1 frame header value %i",
                                   buf[2] >> 4);
-            l->shift = 1;
+            shift = 1;
         }
     }
 
@@ -115,10 +98,10 @@ static int decode_frame(AVCodecContext *avctx,
     V = p->data[2];
     for (j = 0; j < avctx->height; j++) {
         for (i = 0; i < avctx->width / 2; i++) {
-            Y[i * 2] = wnv1_get_code(l, prev_y);
-            prev_u = U[i] = wnv1_get_code(l, prev_u);
-            prev_y = Y[(i * 2) + 1] = wnv1_get_code(l, Y[i * 2]);
-            prev_v = V[i] = wnv1_get_code(l, prev_v);
+            Y[i * 2] = wnv1_get_code(&gb, shift, prev_y);
+            prev_u = U[i] = wnv1_get_code(&gb, shift, prev_u);
+            prev_y = Y[(i * 2) + 1] = wnv1_get_code(&gb, shift, Y[i * 2]);
+            prev_v = V[i] = wnv1_get_code(&gb, shift, prev_v);
         }
         Y += p->linesize[0];
         U += p->linesize[1];
@@ -127,33 +110,36 @@ static int decode_frame(AVCodecContext *avctx,
 
 
     *got_frame      = 1;
-    av_free(rbuf);
 
     return buf_size;
 }
 
+static av_cold void wnv1_init_static(void)
+{
+    INIT_VLC_STATIC_FROM_LENGTHS(&code_vlc, CODE_VLC_BITS, 16,
+                                 &code_tab[0][1], 2,
+                                 &code_tab[0][0], 2, 1,
+                                 -7, INIT_VLC_OUTPUT_LE, 1 << CODE_VLC_BITS);
+}
+
 static av_cold int decode_init(AVCodecContext *avctx)
 {
-    static VLC_TYPE code_table[1 << CODE_VLC_BITS][2];
+    static AVOnce init_static_once = AV_ONCE_INIT;
 
     avctx->pix_fmt = AV_PIX_FMT_YUV422P;
 
-    code_vlc.table           = code_table;
-    code_vlc.table_allocated = 1 << CODE_VLC_BITS;
-    init_vlc(&code_vlc, CODE_VLC_BITS, 16,
-             &code_tab[0][1], 4, 2,
-             &code_tab[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
+    ff_thread_once(&init_static_once, wnv1_init_static);
 
     return 0;
 }
 
-AVCodec ff_wnv1_decoder = {
+const AVCodec ff_wnv1_decoder = {
     .name           = "wnv1",
     .long_name      = NULL_IF_CONFIG_SMALL("Winnov WNV1"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_WNV1,
-    .priv_data_size = sizeof(WNV1Context),
     .init           = decode_init,
     .decode         = decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1,
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };