From: Michael Fabian 'Xaymar' Dirks <michael.di...@xaymar.com> Adds the "timestamp_precision" option to matroskaenc, which allows users to increase the time stamp precision up to 1 nanosecond. This aids with certain demuxers being unable to detect constant rate. It is a work around fix for the problems reported in 259, 6406, 7927, 8909 and 9124.
Signed-off-by: Michael Fabian 'Xaymar' Dirks <michael.di...@xaymar.com> --- libavformat/matroskaenc.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c index b4284a8778..8e2813c36e 100644 --- a/libavformat/matroskaenc.c +++ b/libavformat/matroskaenc.c @@ -158,6 +158,8 @@ typedef struct MatroskaMuxContext { int default_mode; uint32_t segment_uid[4]; + + AVRational time_base; } MatroskaMuxContext; /** 2 bytes * 7 for EBML IDs, 7 1-byte EBML lengths, 6 1-byte uint, @@ -1816,6 +1818,7 @@ static int mkv_write_header(AVFormatContext *s) const AVDictionaryEntry *tag; int ret, i, version = 2; int64_t creation_time; + int64_t time_base = 1; if (mkv->mode != MODE_WEBM || av_dict_get(s->metadata, "stereo_mode", NULL, 0) || @@ -1852,7 +1855,10 @@ static int mkv_write_header(AVFormatContext *s) return ret; pb = mkv->info.bc; - put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, 1000000); + time_base = av_rescale_q(time_base, mkv->time_base, (AVRational){1, 1000000000}); + av_log(s, AV_LOG_DEBUG, "TimestampScale is: %" PRId64 " ns\n", time_base); + put_ebml_uint(pb, MATROSKA_ID_TIMECODESCALE, time_base); + if ((tag = av_dict_get(s->metadata, "title", NULL, 0))) put_ebml_string(pb, MATROSKA_ID_TITLE, tag->value); if (!(s->flags & AVFMT_FLAG_BITEXACT)) { @@ -1885,11 +1891,11 @@ static int mkv_write_header(AVFormatContext *s) int64_t metadata_duration = get_metadata_duration(s); if (s->duration > 0) { - int64_t scaledDuration = av_rescale(s->duration, 1000, AV_TIME_BASE); + int64_t scaledDuration = av_rescale_q(s->duration, AV_TIME_BASE_Q, mkv->time_base); put_ebml_float(pb, MATROSKA_ID_DURATION, scaledDuration); av_log(s, AV_LOG_DEBUG, "Write early duration from recording time = %" PRIu64 "\n", scaledDuration); } else if (metadata_duration > 0) { - int64_t scaledDuration = av_rescale(metadata_duration, 1000, AV_TIME_BASE); + int64_t scaledDuration = av_rescale_q(metadata_duration, AV_TIME_BASE_Q, mkv->time_base); put_ebml_float(pb, MATROSKA_ID_DURATION, scaledDuration); av_log(s, AV_LOG_DEBUG, "Write early duration from metadata = %" PRIu64 "\n", scaledDuration); } else if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) { @@ -1950,12 +1956,12 @@ static int mkv_write_header(AVFormatContext *s) // after 4k and on a keyframe if (IS_SEEKABLE(pb, mkv)) { if (mkv->cluster_time_limit < 0) - mkv->cluster_time_limit = 5000; + mkv->cluster_time_limit = av_rescale_q(5000, (AVRational){1, 1000}, mkv->time_base); if (mkv->cluster_size_limit < 0) mkv->cluster_size_limit = 5 * 1024 * 1024; } else { if (mkv->cluster_time_limit < 0) - mkv->cluster_time_limit = 1000; + mkv->cluster_time_limit = av_rescale_q(1000, (AVRational){1, 1000}, mkv->time_base); if (mkv->cluster_size_limit < 0) mkv->cluster_size_limit = 32 * 1024; } @@ -2736,8 +2742,8 @@ static int mkv_init(struct AVFormatContext *s) track->uid = mkv_get_uid(mkv->tracks, i, &c); } - // ms precision is the de-facto standard timescale for mkv files - avpriv_set_pts_info(st, 64, 1, 1000); + // Use user-defined timescale. + avpriv_set_pts_info(st, 64, mkv->time_base.num, mkv->time_base.den); if (st->codecpar->codec_type == AVMEDIA_TYPE_ATTACHMENT) { if (mkv->mode == MODE_WEBM) { @@ -2757,6 +2763,10 @@ static int mkv_init(struct AVFormatContext *s) track->track_num_size = ebml_num_size(track->track_num); } + // Scale the configured cluster_time_limit. + if (mkv->cluster_time_limit >= 0) + mkv->cluster_time_limit = av_rescale_q(mkv->cluster_time_limit, (AVRational){1, 1000}, mkv->time_base); + if (mkv->is_dash && nb_tracks != 1) return AVERROR(EINVAL); @@ -2824,6 +2834,7 @@ static const AVOption options[] = { { "infer", "For each track type, mark the first track of disposition default as default; if none exists, mark the first track as default.", 0, AV_OPT_TYPE_CONST, { .i64 = DEFAULT_MODE_INFER }, 0, 0, FLAGS, "default_mode" }, { "infer_no_subs", "For each track type, mark the first track of disposition default as default; for audio and video: if none exists, mark the first track as default.", 0, AV_OPT_TYPE_CONST, { .i64 = DEFAULT_MODE_INFER_NO_SUBS }, 0, 0, FLAGS, "default_mode" }, { "passthrough", "Use the disposition flag as-is", 0, AV_OPT_TYPE_CONST, { .i64 = DEFAULT_MODE_PASSTHROUGH }, 0, 0, FLAGS, "default_mode" }, + { "timestamp_precision", "Timestamp precision to use for the entire container", OFFSET(time_base), AV_OPT_TYPE_RATIONAL, { .dbl = 0.001 }, 0.000000001, 1.0, FLAGS}, { NULL }, }; -- 2.31.1.windows.1 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".