Opened 7 years ago
Last modified 7 years ago
#6703 new defect
ffmpeg rounds duration_ts and duration
| Reported by: | mucikiki | Owned by: | |
|---|---|---|---|
| Priority: | normal | Component: | avformat |
| Version: | git-master | Keywords: | mov edts duration regression |
| Cc: | Blocked By: | ||
| Blocking: | Reproduced by developer: | no | |
| Analyzed by developer: | no |
Description
Summary of the bug:
if you use NTSC videos (29.97fps), duration_ts and duration are rounded, so codec_time_base is wrong.
For example, if input video has duration=74.574500, it become duration=74.575000 (note the last 3 zeros), if duration=60.093367 it become duration=60.094000.
How to reproduce:
/usr/local/bin/ffmpeg -i input.mp4 -r ntsc -c:v libx264 -profile:v main -level:v 3.1 -crf 18 output.mp4
ffmpeg version N-85647-g59d219b
built with gcc 4.9.2 (Debian 4.9.2-10)
Attachments (4)
Change History (13)
comment:1 by , 7 years ago
| Keywords: | ntsc duration duration_ts codec_time_base removed |
|---|
by , 7 years ago
by , 7 years ago
comment:2 by , 7 years ago
Yes, this is the command, with the complete output:
/usr/local/bin/ffmpeg -i /var/www/html/1/download/test1.mp4 -c:v libx264 -profile:v main -level:v 3.1 -crf 18 /var/www/html/1/download/test2.mp4
ffmpeg version N-85647-g59d219b Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 4.9.2 (Debian 4.9.2-10)
configuration: --prefix=/root/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/root/ffmpeg_build/include --extra-ldflags=-L/root/ffmpeg_build/lib --bindir=/root/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-nonfree
libavutil 55. 61.100 / 55. 61.100
libavcodec 57. 93.100 / 57. 93.100
libavformat 57. 72.101 / 57. 72.101
libavdevice 57. 7.100 / 57. 7.100
libavfilter 6. 87.100 / 6. 87.100
libswscale 4. 7.101 / 4. 7.101
libswresample 2. 8.100 / 2. 8.100
libpostproc 54. 6.100 / 54. 6.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/var/www/html/1/download/test1.mp4':
Metadata:
major_brand : mp42
minor_version : 0
compatible_brands: mp42mp41
creation_time : 2017-09-30T12:49:58.000000Z
Duration: 00:00:06.24, start: 0.000000, bitrate: 47 kb/s
Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 1280x720, 30 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc (default)
Metadata:
creation_time : 2017-09-30T12:49:58.000000Z
handler_name : Alias Data Handler
encoder : AVC Coding
Stream mapping:
Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
Press [q] to stop, [?] for help
[libx264 @ 0x3c858a0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
[libx264 @ 0x3c858a0] profile Main, level 3.1
[libx264 @ 0x3c858a0] 264 - core 148 - H.264/MPEG-4 AVC codec - Copyleft 2003-2017 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x1:0x111 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=3 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=18.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to '/var/www/html/1/download/test2.mp4':
Metadata:
major_brand : mp42
minor_version : 0
compatible_brands: mp42mp41
encoder : Lavf57.72.101
Stream #0:0(eng): Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1280x720, q=-1--1, 29.97 fps, 30k tbn, 29.97 tbc (default)
Metadata:
creation_time : 2017-09-30T12:49:58.000000Z
handler_name : Alias Data Handler
encoder : Lavc57.93.100 libx264
Side data:
cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
frame= 187 fps=126 q=-1.0 Lsize= 14kB time=00:00:06.13 bitrate= 18.3kbits/s speed=4.13x
video:11kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 27.948391%
[libx264 @ 0x3c858a0] frame I:1 Avg QP: 5.78 size: 1351
[libx264 @ 0x3c858a0] frame P:47 Avg QP:10.86 size: 63
[libx264 @ 0x3c858a0] frame B:139 Avg QP:10.70 size: 43
[libx264 @ 0x3c858a0] consecutive B-frames: 0.5% 1.1% 0.0% 98.4%
[libx264 @ 0x3c858a0] mb I I16..4: 99.3% 0.0% 0.7%
[libx264 @ 0x3c858a0] mb P I16..4: 0.1% 0.0% 0.0% P16..4: 0.1% 0.0% 0.0% 0.0% 0.0% skip:99.7%
[libx264 @ 0x3c858a0] mb B I16..4: 0.0% 0.0% 0.0% B16..8: 0.1% 0.0% 0.0% direct: 0.0% skip:99.9% L0:29.0% L1:71.0% BI: 0.0%
[libx264 @ 0x3c858a0] coded y,uvDC,uvAC intra: 0.3% 3.8% 0.9% inter: 0.0% 0.0% 0.0%
[libx264 @ 0x3c858a0] i16 v,h,dc,p: 93% 6% 2% 0%
[libx264 @ 0x3c858a0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 36% 22% 42% 0% 0% 0% 0% 0% 0%
[libx264 @ 0x3c858a0] i8c dc,h,v,p: 76% 6% 18% 0%
[libx264 @ 0x3c858a0] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x3c858a0] ref P L0: 81.7% 0.6% 17.1% 0.6%
[libx264 @ 0x3c858a0] ref B L0: 51.6% 48.4%
[libx264 @ 0x3c858a0] ref B L1: 99.6% 0.4%
[libx264 @ 0x3c858a0] kb/s:13.25
And these are both durations (obtained via ffprobe):
ffprobe -show_streams -i "/var/www/html/1/download/test1.mp4"
duration=6.239567
ffprobe -show_streams -i "/var/wwwt/html/1/download/test2.mp4"
duration=6.240000
You can find both videos attached.
comment:3 by , 7 years ago
You can also see the duration in this way:
root@Debian2:/home/t2s4e0p# ffprobe /var/www/html/1/download/test2.mp4 -show_entries format=duration -v 0 [FORMAT] duration=6.240000 [/FORMAT] root@Debian2:/home/t2s4e0p# ffprobe /var/www/html/1/download/test1.mp4 -show_entries format=duration -v 0 [FORMAT] duration=6.239567 [/FORMAT]
comment:4 by , 7 years ago
| Component: | undetermined → avformat |
|---|---|
| Keywords: | mov edts duration regression added |
| Version: | unspecified → git-master |
As described above, this is a regression since a53201879ca36af6fcc8a0d4bcc1fa6d759b67ec but I don't know if the file has an issue or if the shown duration is wrong (or if there was a bug that is fixed now).
comment:5 by , 7 years ago
I try to concat test1.mp4 with themself, and to concat test2.mp4 with themself, and I check both videos with MediaInfo (to have a different point of view).
With test1concat.mp4, the frame rate mode is still Costant, but with test2concat.mp4 is now Variable:
Frame rate : 29.970 (29970/1000) FPS
Minimum frame rate : 29.586 FPS
Maximum frame rate : 29.970 FPS
So I think this is an issue of the file.
by , 7 years ago
| Attachment: | test1concat.mp4 added |
|---|
by , 7 years ago
| Attachment: | test2concat.mp4 added |
|---|
comment:6 by , 7 years ago
First concat:
/usr/local/bin/ffmpeg -f concat -i /var/www/html/1/download/test-1-2.txt -c copy /var/www/html/1/download/test1concat.mp4
ffmpeg version N-85647-g59d219b Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 4.9.2 (Debian 4.9.2-10)
configuration: --prefix=/root/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/root/ffmpeg_build/include --extra-ldflags=-L/root/ffmpeg_build/lib --bindir=/root/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-nonfree
libavutil 55. 61.100 / 55. 61.100
libavcodec 57. 93.100 / 57. 93.100
libavformat 57. 72.101 / 57. 72.101
libavdevice 57. 7.100 / 57. 7.100
libavfilter 6. 87.100 / 6. 87.100
libswscale 4. 7.101 / 4. 7.101
libswresample 2. 8.100 / 2. 8.100
libpostproc 54. 6.100 / 54. 6.100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x3912a20] Auto-inserting h264_mp4toannexb bitstream filter
Input #0, concat, from '/var/www/html/1/download/test-1-2.txt':
Duration: N/A, start: 0.000000, bitrate: 30 kb/s
Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 1280x720, 30 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc
Metadata:
creation_time : 2017-09-30T12:49:58.000000Z
handler_name : Alias Data Handler
encoder : AVC Coding
Output #0, mp4, to '/var/www/html/1/download/test1concat.mp4':
Metadata:
encoder : Lavf57.72.101
Stream #0:0(eng): Video: h264 (Main) ([33][0][0][0] / 0x0021), yuv420p(tv, bt709), 1280x720, q=2-31, 30 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 30k tbc
Metadata:
creation_time : 2017-09-30T12:49:58.000000Z
handler_name : Alias Data Handler
encoder : AVC Coding
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x39182c0] Auto-inserting h264_mp4toannexb bitstream filter
frame= 374 fps=0.0 q=-1.0 Lsize= 51kB time=00:00:12.41 bitrate= 33.7kbits/s speed=1.17e+03x
video:47kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 8.141509%
Second concat:
root@Debian2:/home/t2s4e0p# /usr/local/bin/ffmpeg -f concat -i /var/www/html/1/download/test-1-2b.txt -c copy /var/www/html/1/download/test2concat.mp4
ffmpeg version N-85647-g59d219b Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 4.9.2 (Debian 4.9.2-10)
configuration: --prefix=/root/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/root/ffmpeg_build/include --extra-ldflags=-L/root/ffmpeg_build/lib --bindir=/root/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-nonfree
libavutil 55. 61.100 / 55. 61.100
libavcodec 57. 93.100 / 57. 93.100
libavformat 57. 72.101 / 57. 72.101
libavdevice 57. 7.100 / 57. 7.100
libavfilter 6. 87.100 / 6. 87.100
libswscale 4. 7.101 / 4. 7.101
libswresample 2. 8.100 / 2. 8.100
libpostproc 54. 6.100 / 54. 6.100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x2dcea20] Auto-inserting h264_mp4toannexb bitstream filter
Input #0, concat, from '/var/www/html/1/download/test-1-2b.txt':
Duration: N/A, start: 0.000000, bitrate: 14 kb/s
Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 1280x720, 14 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 59.94 tbc
Metadata:
handler_name : VideoHandler
Output #0, mp4, to '/var/www/html/1/download/test2concat.mp4':
Metadata:
encoder : Lavf57.72.101
Stream #0:0(eng): Video: h264 (Main) ([33][0][0][0] / 0x0021), yuv420p, 1280x720, q=2-31, 14 kb/s, 29.97 fps, 29.97 tbr, 30k tbn, 30k tbc
Metadata:
handler_name : VideoHandler
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x2df9180] Auto-inserting h264_mp4toannexb bitstream filter
frame= 374 fps=0.0 q=-1.0 Lsize= 27kB time=00:00:12.37 bitrate= 17.7kbits/s speed=1.57e+03x
video:21kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 24.252748%
I noticed a great difference in muxing overhead, maybe it can be useful.
comment:7 by , 7 years ago
Last thing, I also test the newer version of ffmpeg, with same results:
ffmpeg version N-87628-g148c8e8 Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 6.3.0 (Debian 6.3.0-18) 20170516
configuration: --prefix=/root/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/root/ffmpeg_build/include --extra-ldflags=-L/root/ffmpeg_build/lib --bindir=/root/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-nonfree
libavutil 55. 77.101 / 55. 77.101
libavcodec 57.106.104 / 57.106.104
libavformat 57. 82.102 / 57. 82.102
libavdevice 57. 9.101 / 57. 9.101
libavfilter 6.106.100 / 6.106.100
libswscale 4. 7.103 / 4. 7.103
libswresample 2. 8.100 / 2. 8.100
libpostproc 54. 6.100 / 54. 6.100
comment:8 by , 7 years ago
I finally found a workaround, if I use concat protocol everything is ok, the error is only related to concat demuxer.
comment:9 by , 7 years ago
The file produced by ffmpeg after encoding "test2.mp4" has different duration values in "mvhd", "elst" vs in "mdhd" .
This is because ffmpeg is using less-granular "movie timescale" (1000) than the one used for the stream (30000) . The mdhd duration of 187187 is actually correct because there are only 187 samples of 1001 duratino each in stts. However when the ffmpeg MOV muxer adds the mvhd, edts boxes it rounds the duration to 6240, because of the timescale 1000.
mvhd:
Timescale 1000
Duration 6240
mdhd:
Timescale 30000
Duration 187187
=> 187187/ 30000 ~ 6.239567s
elst:
EntryCount 1
Entry[0].SegmentDuration 6240
Entry[0].MediaTime 2002
When we have -advanced_editlist 1 (which is the default), the edit list parsing code will correctly set the stream duration based on edit list segment duration to 6.24s.
When we have -advanced_editlist 0, then the duration is obtained from mdhd or summing up stts durations, so we have a duration of 6.239567
What we can do here is to change ffmpeg MOV muxer to use a more granular timescale.
Please provide the command line you tested together with the complete, uncut console output and explain how we can reproduce the issue you see. Please attach an input sample.