diff --git a/libavcodec/wmv2dec.c b/libavcodec/wmv2dec.c index 4f97d9227c..92daa1639e 100644 --- a/libavcodec/wmv2dec.c +++ b/libavcodec/wmv2dec.c @@ -181,6 +181,14 @@ int ff_wmv2_decode_secondary_picture_header(MpegEncContext *s) } s->dc_table_index = get_bits1(&s->gb); + + // at minimum one bit per macroblock is required at least in a valid frame, + // we discard frames much smaller than this. Frames smaller than 1/8 of the + // smallest "black/skip" frame generally contain not much recoverable content + // while at the same time they have the highest computational requirements + // per byte + if (get_bits_left(&s->gb) * 8LL < (s->width+15)/16 * ((s->height+15)/16)) + return AVERROR_INVALIDDATA; } s->inter_intra_pred = 0; s->no_rounding = 1;