[FFmpeg-devel] [PATCH] libavcodec/h263dec.c: Duplicate the last decoded frame when xvid marks the packet as skipped.

[Thierry Foucu]

Changed the return value when no VOD were encoded in Mpeg4 bistream.
And if we do have already a decoded frames and we are not in xvid_packed
mode, output the existing decoded frame instead of nothing.
---
 libavcodec/h263dec.c       | 9 ++++++++-
 libavcodec/mpeg4videodec.c | 2 +-
 libavcodec/mpegutils.h     | 1 +
 3 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/libavcodec/h263dec.c b/libavcodec/h263dec.c
index c7cf4bc0c2..394a366f9c 100644
--- a/libavcodec/h263dec.c
+++ b/libavcodec/h263dec.c
@@ -506,8 +506,15 @@ retry:
                 s->height= avctx->coded_height;
         }
     }
-    if (ret == FRAME_SKIPPED)
+    if (ret == FRAME_SKIPPED || ret == FRAME_NOT_CODED) {
+        if (s->next_picture_ptr && ret == FRAME_NOT_CODED && !s->divx_packed) {
+            if ((ret = av_frame_ref(pict, s->next_picture_ptr->f)) < 0) {
+                return ret;
+            }
+            *got_frame = 1;
+        }
         return get_consumed_bytes(s, buf_size);
+    }
 
     /* skip if the header was thrashed */
     if (ret < 0) {
diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c
index 82c4f8fc8c..3a9ed12971 100644
--- a/libavcodec/mpeg4videodec.c
+++ b/libavcodec/mpeg4videodec.c
@@ -2394,7 +2394,7 @@ static int decode_vop_header(Mpeg4DecContext *ctx, GetBitContext *gb)
     if (get_bits1(gb) != 1) {
         if (s->avctx->debug & FF_DEBUG_PICT_INFO)
             av_log(s->avctx, AV_LOG_ERROR, "vop not coded\n");
-        return FRAME_SKIPPED;
+        return FRAME_NOT_CODED;
     }
     if (ctx->new_pred)
         decode_new_pred(ctx, gb);
diff --git a/libavcodec/mpegutils.h b/libavcodec/mpegutils.h
index 1bf73fea02..97786135c6 100644
--- a/libavcodec/mpegutils.h
+++ b/libavcodec/mpegutils.h
@@ -32,6 +32,7 @@
  * Return value for header parsers if frame is not coded.
  * */
 #define FRAME_SKIPPED 100
+#define FRAME_NOT_CODED 101
 
 /* picture type */
 #define PICT_TOP_FIELD     1
-- 
2.15.0.rc0.271.g36b669edcc-goog