From aacb2386293d368ef0b643e9bd9ff3610e690dd5 Mon Sep 17 00:00:00 2001 From: Justin Ruggles Date: Tue, 27 Apr 2021 12:15:11 -0400 Subject: [PATCH] movenc: add movie_timescale option instead of hardcoding 1000 There are cases where using 1000 as the MP4 timescale is not accurate enough, for example when one needs sample-accurate audio handling. This adds a new AVOption to the MOV/MP4 muxer to override the movie timescale, but it still defaults to 1000 to maintain current default behavior. --- libavformat/movenc.c | 23 ++++++++++++----------- libavformat/movenc.h | 1 + 2 files changed, 13 insertions(+), 11 deletions(-) diff --git a/libavformat/movenc.c b/libavformat/movenc.c index 8e6ed81..93f93e4 100644 --- a/libavformat/movenc.c +++ b/libavformat/movenc.c @@ -107,6 +107,7 @@ static const AVOption options[] = { { "wallclock", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = MOV_PRFT_SRC_WALLCLOCK}, 0, 0, AV_OPT_FLAG_ENCODING_PARAM, "prft"}, { "pts", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = MOV_PRFT_SRC_PTS}, 0, 0, AV_OPT_FLAG_ENCODING_PARAM, "prft"}, { "empty_hdlr_name", "write zero-length name string in hdlr atoms within mdia and minf atoms", offsetof(MOVMuxContext, empty_hdlr_name), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM}, + { "movie_timescale", "set movie timescale", offsetof(MOVMuxContext, movie_timescale), AV_OPT_TYPE_INT, {.i64 = MOV_TIMESCALE}, 1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM}, { NULL }, }; @@ -3039,7 +3040,7 @@ static int mov_write_tkhd_tag(AVIOContext *pb, MOVMuxContext *mov, MOVTrack *track, AVStream *st) { int64_t duration = av_rescale_rnd(calc_pts_duration(mov, track), - MOV_TIMESCALE, track->timescale, + mov->movie_timescale, track->timescale, AV_ROUND_UP); int version = duration < INT32_MAX ? 0 : 1; int flags = MOV_TKHD_FLAG_IN_MOVIE; @@ -3188,7 +3189,7 @@ static int mov_write_edts_tag(AVIOContext *pb, MOVMuxContext *mov, MOVTrack *track) { int64_t duration = av_rescale_rnd(calc_samples_pts_duration(mov, track), - MOV_TIMESCALE, track->timescale, + mov->movie_timescale, track->timescale, AV_ROUND_UP); int version = duration < INT32_MAX ? 0 : 1; int entry_size, entry_count, size; @@ -3207,7 +3208,7 @@ static int mov_write_edts_tag(AVIOContext *pb, MOVMuxContext *mov, } } - delay = av_rescale_rnd(start_dts + start_ct, MOV_TIMESCALE, + delay = av_rescale_rnd(start_dts + start_ct, mov->movie_timescale, track->timescale, AV_ROUND_DOWN); version |= delay < INT32_MAX ? 0 : 1; @@ -3242,8 +3243,8 @@ static int mov_write_edts_tag(AVIOContext *pb, MOVMuxContext *mov, /* Avoid accidentally ending up with start_ct = -1 which has got a * special meaning. Normally start_ct should end up positive or zero * here, but use FFMIN in case dts is a small positive integer - * rounded to 0 when represented in MOV_TIMESCALE units. */ - av_assert0(av_rescale_rnd(start_dts, MOV_TIMESCALE, track->timescale, AV_ROUND_DOWN) <= 0); + * rounded to 0 when represented in movie timescale units. */ + av_assert0(av_rescale_rnd(start_dts, mov->movie_timescale, track->timescale, AV_ROUND_DOWN) <= 0); start_ct = -FFMIN(start_dts, 0); /* Note, this delay is calculated from the pts of the first sample, * ensuring that we don't reduce the duration for cases with @@ -3477,7 +3478,7 @@ static int mov_write_mvhd_tag(AVIOContext *pb, MOVMuxContext *mov) if (mov->tracks[i].entry > 0 && mov->tracks[i].timescale) { int64_t max_track_len_temp = av_rescale_rnd( calc_pts_duration(mov, &mov->tracks[i]), - MOV_TIMESCALE, + mov->movie_timescale, mov->tracks[i].timescale, AV_ROUND_UP); if (max_track_len < max_track_len_temp) @@ -3506,7 +3507,7 @@ static int mov_write_mvhd_tag(AVIOContext *pb, MOVMuxContext *mov) avio_wb32(pb, mov->time); /* creation time */ avio_wb32(pb, mov->time); /* modification time */ } - avio_wb32(pb, MOV_TIMESCALE); + avio_wb32(pb, mov->movie_timescale); (version == 1) ? avio_wb64(pb, max_track_len) : avio_wb32(pb, max_track_len); /* duration of longest track */ avio_wb32(pb, 0x00010000); /* reserved (preferred rate) 1.0 = normal */ @@ -6115,7 +6116,7 @@ static int mov_create_chapter_track(AVFormatContext *s, int tracknum) track->mode = mov->mode; track->tag = MKTAG('t','e','x','t'); - track->timescale = MOV_TIMESCALE; + track->timescale = mov->movie_timescale; track->par = avcodec_parameters_alloc(); if (!track->par) return AVERROR(ENOMEM); @@ -6179,8 +6180,8 @@ static int mov_create_chapter_track(AVFormatContext *s, int tracknum) AVChapter *c = s->chapters[i]; AVDictionaryEntry *t; - int64_t end = av_rescale_q(c->end, c->time_base, (AVRational){1,MOV_TIMESCALE}); - pkt->pts = pkt->dts = av_rescale_q(c->start, c->time_base, (AVRational){1,MOV_TIMESCALE}); + int64_t end = av_rescale_q(c->end, c->time_base, (AVRational){1,mov->movie_timescale}); + pkt->pts = pkt->dts = av_rescale_q(c->start, c->time_base, (AVRational){1,mov->movie_timescale}); pkt->duration = end - pkt->dts; if ((t = av_dict_get(c->metadata, "title", NULL, 0))) { @@ -6737,7 +6738,7 @@ static int mov_init(AVFormatContext *s) } else if (st->codecpar->codec_type == AVMEDIA_TYPE_DATA) { track->timescale = st->time_base.den; } else { - track->timescale = MOV_TIMESCALE; + track->timescale = mov->movie_timescale; } if (!track->height) track->height = st->codecpar->height; diff --git a/libavformat/movenc.h b/libavformat/movenc.h index cdbc407..af1ea0b 100644 --- a/libavformat/movenc.h +++ b/libavformat/movenc.h @@ -237,6 +237,7 @@ typedef struct MOVMuxContext { int write_tmcd; MOVPrftBox write_prft; int empty_hdlr_name; + int movie_timescale; } MOVMuxContext; #define FF_MOV_FLAG_RTP_HINT (1 << 0) -- 2.20.1 (Apple Git-117)