Make sure that dv encoder initializes all encoded packet data.

The specification does not say which value to use for unused
parts, so fill all unused bytes with 0xff, which is consistent
with what DV usually uses for reserved or unused parts.

Originally committed as revision 20084 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 10 insertions, 1 deletions

diff --git a/libavcodec/dv.c b/libavcodec/dv.c
index 078c30dbb6..b17bbc7074 100644
--- a/libavcodec/dv.c
+++ b/libavcodec/dv.c
@@ -1102,8 +1102,17 @@ static int dv_encode_video_segment(AVCodecContext *avctx, void *arg)
             av_log(NULL, AV_LOG_ERROR, "ac bitstream overflow\n");
     }
 
-    for (j=0; j<5*s->sys->bpm; j++)
+    for (j=0; j<5*s->sys->bpm; j++) {
+       int pos;
+       int size = pbs[j].size_in_bits >> 3;
        flush_put_bits(&pbs[j]);
+       pos = put_bits_count(&pbs[j]) >> 3;
+       if (pos > size) {
+           av_log(avctx, AV_LOG_ERROR, "bitstream written beyond buffer size\n");
+           return -1;
+       }
+       memset(pbs[j].buf + pos, 0xff, size - pos);
+    }
 
     return 0;
 }