add support for files that do not allow more than 4 subframes

[ffmpeg] / libavcodec / mjpegdec.c

diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index ce52a08e8355573af3a90f7a89afd5b57328b820..e57f74f3744cdd15c6b376ad3eff5bd0ba6df5f7 100644 (file)
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -57,6 +57,8 @@ static int build_vlc(VLC *vlc, const uint8_t *bits_table, const uint8_t *val_tab
     for(i=0; i<256; i++)
         huff_sym[i]= i + 16*is_ac;
 
+    if(is_ac) huff_sym[0]= 16*256;
+
     return init_vlc_sparse(vlc, 9, nb_codes, huff_size, 1, 1, huff_code, 2, 2, huff_sym, 2, 2, use_static);
 }
 
@@ -192,8 +194,12 @@ int ff_mjpeg_decode_dht(MJpegDecodeContext *s)
         if(build_vlc(&s->vlcs[class][index], bits_table, val_table, code_max + 1, 0, class > 0) < 0){
             return -1;
         }
-        if(class>0 && build_vlc(&s->vlcs[2][index], bits_table, val_table, code_max + 1, 0, 0) < 0){
+
+        if(class>0){
+            free_vlc(&s->vlcs[2][index]);
+            if(build_vlc(&s->vlcs[2][index], bits_table, val_table, code_max + 1, 0, 0) < 0){
             return -1;
+            }
         }
     }
     return 0;
@@ -415,9 +421,6 @@ static int decode_block(MJpegDecodeContext *s, DCTELEM *block,
         UPDATE_CACHE(re, &s->gb);
         GET_VLC(code, re, &s->gb, s->vlcs[1][ac_index].table, 9, 2)
 
-        /* EOB */
-        if (code == 0x10)
-            break;
         i += ((unsigned)code) >> 4;
             code &= 0xf;
         if(code){
@@ -432,12 +435,7 @@ static int decode_block(MJpegDecodeContext *s, DCTELEM *block,
 
             LAST_SKIP_BITS(re, &s->gb, code)
 
-            if (i >= 63) {
-                if(i == 63){
-                    j = s->scantable.permutated[63];
-                    block[j] = level * quant_matrix[j];
-                    break;
-                }
+            if (i > 63) {
                 av_log(s->avctx, AV_LOG_ERROR, "error count: %d\n", i);
                 return -1;
             }
@@ -1527,7 +1525,7 @@ av_cold int ff_mjpeg_decode_end(AVCodecContext *avctx)
     av_freep(&s->ljpeg_buffer);
     s->ljpeg_buffer_size=0;
 
-    for(i=0;i<2;i++) {
+    for(i=0;i<3;i++) {
         for(j=0;j<4;j++)
             free_vlc(&s->vlcs[i][j]);
     }