[FFmpeg-devel] [PATCH] lavf/movenc: Replace dts by pts to calculate duration
manuelyuan
manuelyuan at 163.com
Thu Nov 28 04:34:34 EET 2019
In this case, the input video is of dynamic frame rate and we don't want to
duplicate or drop frames, but the output video duration calculated by DTS is
incorrect, I solved it by using PTS.
There are many UGC videos with dynamic frame rates, which are represented by
PTS jumps. After transcoding with ffmpeg -vsync 0 or -vsync 2, the output
video duration becomes longer.By reading the code of x264/encoder/encoder.c,
I found that in order to predict the B frame, x264 needs to ensure that there
are enough reference frames when DTS = 0, so the DTS of these reference frames
will subtract the cache time. However, the cache time includes the part of PTS
jumps, which results in the abnormal small DTS.
Signed-off-by: Mengyang Yuan <manuelyuan at 163.com>
---
libavformat/movenc.c | 23 ++++++++++++++---------
libavformat/movenc.h | 2 ++
tests/ref/fate/binsub-movtextenc | 2 +-
tests/ref/fate/movenc | 20 ++++++++++----------
tests/ref/lavf/mov | 4 ++--
tests/ref/lavf/mp4 | 4 ++--
6 files changed, 31 insertions(+), 24 deletions(-)
diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index 715bec1c2f..206aa48d8c 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -1015,7 +1015,7 @@ static int get_cluster_duration(MOVTrack *track, int cluster_idx)
return 0;
if (cluster_idx + 1 == track->entry)
- next_dts = track->track_duration + track->start_dts;
+ next_dts = track->end_dts;
else
next_dts = track->cluster[cluster_idx + 1].dts;
@@ -5149,8 +5149,7 @@ static int mov_flush_fragment(AVFormatContext *s, int force)
mov->mdat_size = 0;
for (i = 0; i < mov->nb_streams; i++) {
if (mov->tracks[i].entry)
- mov->tracks[i].frag_start += mov->tracks[i].start_dts +
- mov->tracks[i].track_duration -
+ mov->tracks[i].frag_start += mov->tracks[i].end_dts -
mov->tracks[i].cluster[0].dts;
mov->tracks[i].entry = 0;
mov->tracks[i].end_reliable = 0;
@@ -5208,7 +5207,7 @@ static int mov_flush_fragment(AVFormatContext *s, int force)
int64_t duration = 0;
if (track->entry)
- duration = track->start_dts + track->track_duration -
+ duration = track->end_dts -
track->cluster[0].dts;
if (mov->flags & FF_MOV_FLAG_SEPARATE_MOOF) {
if (!track->mdat_buf)
@@ -5281,7 +5280,7 @@ static int check_pkt(AVFormatContext *s, AVPacket *pkt)
ref = trk->cluster[trk->entry - 1].dts;
} else if ( trk->start_dts != AV_NOPTS_VALUE
&& !trk->frag_discont) {
- ref = trk->start_dts + trk->track_duration;
+ ref = trk->end_dts;
} else
ref = pkt->dts; // Skip tests for the first packet
@@ -5494,7 +5493,7 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
* of the last packet of the previous fragment based on track_duration,
* which might not exactly match our dts. Therefore adjust the dts
* of this packet to be what the previous packets duration implies. */
- trk->cluster[trk->entry].dts = trk->start_dts + trk->track_duration;
+ trk->cluster[trk->entry].dts = trk->end_dts;
/* We also may have written the pts and the corresponding duration
* in sidx/tfrf/tfxd tags; make sure the sidx pts and duration match up with
* the next fragment. This means the cts of the first sample must
@@ -5546,13 +5545,17 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
"this case.\n",
pkt->stream_index, pkt->dts);
}
- trk->track_duration = pkt->dts - trk->start_dts + pkt->duration;
- trk->last_sample_is_subtitle_end = 0;
-
if (pkt->pts == AV_NOPTS_VALUE) {
av_log(s, AV_LOG_WARNING, "pts has no value\n");
pkt->pts = pkt->dts;
}
+ if (trk->start_pts == AV_NOPTS_VALUE) {
+ trk->start_pts = pkt->pts;
+ }
+ trk->track_duration = FFMAX(pkt->pts - trk->start_pts + pkt->duration, trk->track_duration);
+ trk->end_dts = pkt->dts + pkt->duration;
+ trk->last_sample_is_subtitle_end = 0;
+
if (pkt->dts != pkt->pts)
trk->flags |= MOV_TRACK_CTTS;
trk->cluster[trk->entry].cts = pkt->pts - pkt->dts;
@@ -6295,7 +6298,9 @@ static int mov_init(AVFormatContext *s)
* this is updated. */
track->hint_track = -1;
track->start_dts = AV_NOPTS_VALUE;
+ track->start_pts = AV_NOPTS_VALUE;
track->start_cts = AV_NOPTS_VALUE;
+ track->end_dts = AV_NOPTS_VALUE;
track->end_pts = AV_NOPTS_VALUE;
track->dts_shift = AV_NOPTS_VALUE;
if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
diff --git a/libavformat/movenc.h b/libavformat/movenc.h
index 68d6f23a5a..ddad2631d7 100644
--- a/libavformat/movenc.h
+++ b/libavformat/movenc.h
@@ -116,7 +116,9 @@ typedef struct MOVTrack {
uint32_t tref_tag;
int tref_id; ///< trackID of the referenced track
int64_t start_dts;
+ int64_t start_pts;
int64_t start_cts;
+ int64_t end_dts;
int64_t end_pts;
int end_reliable;
int64_t dts_shift;
diff --git a/tests/ref/fate/binsub-movtextenc b/tests/ref/fate/binsub-movtextenc
index dacee0931e..d094205f5f 100644
--- a/tests/ref/fate/binsub-movtextenc
+++ b/tests/ref/fate/binsub-movtextenc
@@ -1 +1 @@
-66b25412f7ca699ee525ba162246edb6
+4577e340441dff191080ec02ae6b716a
diff --git a/tests/ref/fate/movenc b/tests/ref/fate/movenc
index 5e8f324ea3..e5395aa521 100644
--- a/tests/ref/fate/movenc
+++ b/tests/ref/fate/movenc
@@ -12,7 +12,7 @@ write_data len 36, time nopts, type header atom ftyp
write_data len 2629, time nopts, type header atom -
write_data len 908, time 1000000, type sync atom moof
write_data len 110, time nopts, type trailer atom -
-c184e168ac1e5bb3d9c70e580ab6179c 3683 non-empty-moov-no-elst
+be2119166851ee710a0cd96f5c3755a6 3683 non-empty-moov-no-elst
write_data len 20, time nopts, type header atom ftyp
write_data len 1171, time nopts, type header atom -
write_data len 728, time 0, type sync atom moof
@@ -108,8 +108,8 @@ c3681590a292cb9ca19a5a982e530166 1219 delay-moov-elst-signal-init-discont
write_data len 996, time 966667, type sync atom sidx
aa5462cc0d2144f72154d9c309edb57d 996 delay-moov-elst-signal-second-frag-discont
write_data len 110, time nopts, type trailer atom -
-write_data len 1243, time nopts, type header atom ftyp
-dac14c8795d5cbd91ae770c6e2880c62 1243 delay-moov-elst-signal-init-discont-largets
+write_data len 1219, time nopts, type header atom ftyp
+c3681590a292cb9ca19a5a982e530166 1219 delay-moov-elst-signal-init-discont-largets
write_data len 996, time 279621233333, type sync atom sidx
41cac4c3df656a87bb38363fdcd745e6 996 delay-moov-elst-signal-second-frag-discont-largets
write_data len 110, time nopts, type trailer atom -
@@ -119,10 +119,10 @@ write_data len 996, time 5166667, type sync atom sidx
write_data len 148, time nopts, type trailer atom -
f12d4a0e054abcc508cc0d28cb320e57 4935 vfr
write_data len 1219, time nopts, type header atom ftyp
-write_data len 2572, time -333333, type sync atom sidx
-write_data len 996, time 5166667, type sync atom sidx
+write_data len 3472, time -333333, type sync atom sidx
+write_data len 1460, time 5133333, type sync atom sidx
write_data len 148, time nopts, type trailer atom -
-f12d4a0e054abcc508cc0d28cb320e57 4935 vfr-noduration
+202e3030545f4237eea43efba08f9f88 6299 vfr-noduration
write_data len 1231, time nopts, type header atom ftyp
write_data len 1500, time -333333, type sync atom moof
write_data len 1500, time nopts, type unknown atom -
@@ -133,13 +133,13 @@ write_data len 1004, time nopts, type unknown atom -
write_data len 148, time nopts, type trailer atom -
3c2c3f98c8a047f0ecefff07570fd457 9299 large_frag
write_data len 1231, time nopts, type header atom ftyp
-write_data len 684, time -33333, type sync atom moof
-write_data len 504, time 800000, type boundary atom moof
-write_data len 420, time 1266667, type boundary atom moof
+write_data len 620, time -33333, type sync atom moof
+write_data len 432, time 500000, type boundary atom moof
+write_data len 480, time 1166667, type boundary atom moof
write_data len 668, time 1566667, type sync atom moof
write_data len 440, time 2233333, type boundary atom moof
write_data len 262, time nopts, type trailer atom -
-edd19deae2b70afcf2cd744b89b7013d 4209 vfr-noduration-interleave
+2e93b0e5027b4e27a0dd23e9f749a84d 4133 vfr-noduration-interleave
write_data len 1231, time nopts, type header atom ftyp
write_data len 916, time 0, type sync atom moof
write_data len 908, time 1000000, type sync atom moof
diff --git a/tests/ref/lavf/mov b/tests/ref/lavf/mov
index 75a0c4892d..13ab0f4e8f 100644
--- a/tests/ref/lavf/mov
+++ b/tests/ref/lavf/mov
@@ -1,7 +1,7 @@
-11bd76730274924e02623172b82b5236 *tests/data/lavf/lavf.mov
+b5bc7dbee83ca51ce0ec3270ff4cb68a *tests/data/lavf/lavf.mov
357539 tests/data/lavf/lavf.mov
tests/data/lavf/lavf.mov CRC=0xbb2b949b
-6efa586655e3db043cb29668f5216610 *tests/data/lavf/lavf.mov
+5210f9308b6d26d1eb6c1e4584879bd7 *tests/data/lavf/lavf.mov
366621 tests/data/lavf/lavf.mov
tests/data/lavf/lavf.mov CRC=0xa9793231
c80c625ded376602e71d5aa6ac6fdb1c *tests/data/lavf/lavf.mov
diff --git a/tests/ref/lavf/mp4 b/tests/ref/lavf/mp4
index 8482812380..0275ace9aa 100644
--- a/tests/ref/lavf/mp4
+++ b/tests/ref/lavf/mp4
@@ -1,7 +1,7 @@
-ebca72c186a4f3ba9bb17d9cb5b74fef *tests/data/lavf/lavf.mp4
+e469124650c123ad87974930b8faae2e *tests/data/lavf/lavf.mp4
312457 tests/data/lavf/lavf.mp4
tests/data/lavf/lavf.mp4 CRC=0x9d9a638a
-9944512475d82d2d601f3c96101bdf9c *tests/data/lavf/lavf.mp4
+dd1c6780572514682205ec9f3681a9a2 *tests/data/lavf/lavf.mp4
321343 tests/data/lavf/lavf.mp4
tests/data/lavf/lavf.mp4 CRC=0xe8130120
7b3e71f294901067046c09f03a426bdc *tests/data/lavf/lavf.mp4
--
2.17.2 (Apple Git-113)
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