warn on interlaced streams

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@5337 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavcodec/h264.c

@@ -7283,6 +7283,8 @@ static inline int decode_seq_parameter_set(H264Context *h){
         return -1;
 
     sps->frame_mbs_only_flag= get_bits1(&s->gb);
+    if(!sps->frame_mbs_only_flag)
+        av_log(h->s.avctx, AV_LOG_ERROR, "interlacing is not supported, picture will probably be garbage\n");
     if(!sps->frame_mbs_only_flag)
         sps->mb_aff= get_bits1(&s->gb);
     else