diff options
| -rw-r--r-- | libavformat/matroskadec.c | 23 | ||||
| -rw-r--r-- | libavformat/matroskaenc.c | 5 | ||||
| -rw-r--r-- | libavformat/srtenc.c | 1 |
3 files changed, 26 insertions, 3 deletions
diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c index 1d0dbb3296..c4e0438c1d 100644 --- a/libavformat/matroskadec.c +++ b/libavformat/matroskadec.c @@ -2105,10 +2105,29 @@ static int matroska_parse_block(MatroskaDemuxContext *matroska, uint8_t *data, else pkt->pts = timecode; pkt->pos = pos; - if (st->codec->codec_id == AV_CODEC_ID_SUBRIP) + if (st->codec->codec_id == AV_CODEC_ID_SUBRIP) { + /* + * For backward compatibility. + * Historically, we have put subtitle duration + * in convergence_duration, on the off chance + * that the time_scale is less than 1us, which + * could result in a 32bit overflow on the + * normal duration field. + */ pkt->convergence_duration = lace_duration; - else if (track->type != MATROSKA_TRACK_TYPE_SUBTITLE) + } + + if (track->type != MATROSKA_TRACK_TYPE_SUBTITLE || + lace_duration <= INT_MAX) { + /* + * For non subtitle tracks, just store the duration + * as normal. + * + * If it's a subtitle track and duration value does + * not overflow a uint32, then also store it normally. + */ pkt->duration = lace_duration; + } if (st->codec->codec_id == AV_CODEC_ID_SSA) matroska_fix_ass_packet(matroska, pkt, lace_duration); diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c index 397793119e..79ce9f5cae 100644 --- a/libavformat/matroskaenc.c +++ b/libavformat/matroskaenc.c @@ -1168,7 +1168,10 @@ static int mkv_write_packet_internal(AVFormatContext *s, AVPacket *pkt) duration = mkv_write_srt_blocks(s, pb, pkt); } else { ebml_master blockgroup = start_ebml_master(pb, MATROSKA_ID_BLOCKGROUP, mkv_blockgroup_size(pkt->size)); - duration = pkt->convergence_duration; + /* For backward compatibility, prefer convergence_duration. */ + if (pkt->convergence_duration > 0) { + duration = pkt->convergence_duration; + } mkv_write_block(s, pb, MATROSKA_ID_BLOCK, pkt, 0); put_ebml_uint(pb, MATROSKA_ID_BLOCKDURATION, duration); end_ebml_master(pb, blockgroup); diff --git a/libavformat/srtenc.c b/libavformat/srtenc.c index 6b8278fa80..0b094b00bf 100644 --- a/libavformat/srtenc.c +++ b/libavformat/srtenc.c @@ -65,6 +65,7 @@ static int srt_write_packet(AVFormatContext *avf, AVPacket *pkt) int len; if (d <= 0) + /* For backward compatibility, fallback to convergence_duration. */ d = pkt->convergence_duration; if (s == AV_NOPTS_VALUE || d <= 0) { av_log(avf, AV_LOG_ERROR, "Insufficient timestamps.\n"); |