#2873 closed enhancement (fixed)
ffmpeg concat demuxer fails: mpeg files with different audio and video stream order
| Reported by: | kadmandux | Owned by: | |
|---|---|---|---|
| Priority: | wish | Component: | avformat |
| Version: | git-master | Keywords: | concat demuxer |
| Cc: | Blocked By: | ||
| Blocking: | Reproduced by developer: | no | |
| Analyzed by developer: | no |
Description
Summary of the bug:
I've 2 MPEG files with different order in audio and video stream, which I want to join:
ffprobe MU2000134b.mpg
Input #0, mpeg, from 'MU2000134b.mpg':
Duration: 00:00:40.14, start: 0.500000, bitrate: 7713 kb/s
Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p, 720x576 [SAR 64:45 DAR 16:9], max. 9100 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
Stream #0:1[0x80]: Audio: ac3, 48000 Hz, stereo, fltp, 256 kb/s
ffprobe MU2000135b.mpg
Input #0, mpeg, from 'MU2000135b.mpg':
Duration: 00:02:09.82, start: 0.500000, bitrate: 7583 kb/s
Stream #0:0[0x80]: Audio: ac3, 48000 Hz, stereo, fltp, 256 kb/s
Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p, 720x576 [SAR 64:45 DAR 16:9], max. 9100 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
How to reproduce:
% ffmpeg -f concat -i lista.txt -c:a copy -c:v copy video.mpg
ffmpeg version N-55393-g3b2e99f Copyright (c) 2000-2013 the FFmpeg developers
built on Aug 8 2013 21:32:57 with gcc 4.7.3 (GCC)
configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
le-iconv --enable-libass --enable-libbluray --enable-libcaca --enable-libfreetyp
e --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --ena
ble-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-l
ibopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libsp
eex --enable-libtheora --enable-libtwolame --enable-libvo-aacenc --enable-libvo-
amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --
enable-libxvid --enable-zlib
libavutil 52. 41.100 / 52. 41.100
libavcodec 55. 24.100 / 55. 24.100
libavformat 55. 13.102 / 55. 13.102
libavdevice 55. 3.100 / 55. 3.100
libavfilter 3. 82.100 / 3. 82.100
libswscale 2. 4.100 / 2. 4.100
libswresample 0. 17.103 / 0. 17.103
libpostproc 52. 3.100 / 52. 3.100
[concat @ 026eb160] Estimating duration from bitrate, this may be inaccurate
Input #0, concat, from 'lista.txt':
Duration: 00:00:00.00, start: 0.000000, bitrate: 256 kb/s
Stream #0:0: Video: mpeg2video (Main), yuv420p, 720x576 [SAR 64:45 DAR 16:9]
, max. 9100 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
Stream #0:1: Audio: ac3, 48000 Hz, stereo, fltp, 256 kb/s
Output #0, mpeg, to 'video.mpg':
Metadata:
encoder : Lavf55.13.102
Stream #0:0: Video: mpeg2video, yuv420p, 720x576 [SAR 64:45 DAR 16:9], q=2-3
1, max. 9100 kb/s, 25 fps, 90k tbn, 25 tbc
Stream #0:1: Audio: ac3, 48000 Hz, stereo, 256 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame= 368 fps=0.0 q=-1.0 size= 14306kB time=00:00:14.90 bitrate=7863.3kbits/
frame= 718 fps=717 q=-1.0 size= 27334kB time=00:00:28.90 bitrate=7747.0kbits/
frame= 915 fps=608 q=-1.0 size= 34646kB time=00:00:36.78 bitrate=7715.9kbits/
[mpeg @ 03a9ba40] buffer underflow i=1 bufi=3763 size=41205
[mpeg @ 03a9ba40] packet too large, ignoring buffer limits to mux it
[mpeg @ 03a9ba40] buffer underflow i=1 bufi=3763 size=41205
[mpeg @ 03a9ba40] buffer underflow i=1 bufi=5788 size=41205
[mpeg @ 03a9ba40] packet too large, ignoring buffer limits to mux it
[mpeg @ 03a9ba40] buffer underflow i=1 bufi=5788 size=41205
[mpeg @ 03a9ba40] buffer underflow i=1 bufi=7825 size=41205
[mpeg @ 03a9ba40] packet too large, ignoring buffer limits to mux it
[mpeg @ 03a9ba40] buffer underflow i=1 bufi=7825 size=41205
[mpeg @ 03a9ba40] buffer underflow i=1 bufi=9862 size=41205
[mpeg @ 03a9ba40] packet too large, ignoring buffer limits to mux it
[mpeg @ 03a9ba40] buffer underflow i=1 bufi=9862 size=41205
[mpeg @ 03a9ba40] buffer underflow i=1 bufi=11899 size=41205
The problem doesn't appears if, before the join operation, you reorder the streams (with "-map" option) to have the same order in both files.
Change History (9)
comment:1 by , 11 years ago
| Component: | FFmpeg → avformat |
|---|---|
| Status: | new → open |
| Type: | defect → enhancement |
| Version: | unspecified → git-master |
comment:2 by , 11 years ago
It seems that there is no stream order concept in mpeg-ps:
http://www.ffmpeg.org/trac/ffmpeg/ticket/2876
So, I think that there should be at least a little automatic guessing when you use the concat demuxer with mpeg files, so that you can join files with same content and simple stream schemes, like the files I use (only 2 streams: 1 video + 1 audio).
comment:3 by , 11 years ago
What do you think about this approach?
1.- Add two simple functions to utils.c for to sort the streams based on id:
int av_compare_streams(const void *st1, const void *st2)
{
return ((((AVStream *)st1)->id > ((AVStream *)st2)->id) ? 1 :
(((AVStream *)st1)->id < ((AVStream *)st2)->id) ? -1 : 0);
}
void av_sort_streams_by_id(AVFormatContext *s)
qsort((void *)s->streams, s->nb_streams, sizeof(s->streams[0]), av_compare_streams);
/*Adjust the indexes */
for (int i=0;i<s->nb_streams;i++) {
s->streams[i]->index = i;
}
}
2.- Add the prototypes to "avformat.h"
void av_sort_streams_by_id(AVFormatContext *s); int av_compare_streams(const void *st1, const void *st2);
3.- Modify ffprobe.c, for to use the new function, from inside "open_input_file" function:
/* Reorder streams if the format requires it (added by kadmandux) * Is the flag AVFMTCTX_NOHEADER a good candidate to use for this purpose? * Or should I define a new specific flag in "avformat.h" */ if (fmt_ctx->ctx_flags & AVFMTCTX_NOHEADER) av_sort_streams_by_id(fmt_ctx);
This code should be executed after the call to "avformat_find_stream_info".
4.- Do the equivalent change in ffmpeg_opt.c, also inside "open_input_file" function.
comment:4 by , 11 years ago
Changing the order of the streams would probably not be as simple as changing the order in the array, but it can probably be done.
Something making the order of streams from MPEG-PS less random would probably be welcome (although I may be missing some drawbacks). Please post patches on the mailing list.
You can make it simpler than you suggested, though: just change avformat_find_stream_info(): if format is MPEG-PS and there was no streams already detected, then reorder at the end.
Unfortunately, for your use, this is still too fragile, IMHO. Unless you have a constraint you did not talk about, you would be better off just acknowledging that MPEG-PS is a very bad format and using another, especially for intermediate files.
comment:5 by , 11 years ago
I did some testing and the stream_id doesn't seem a good candidate to sort the streams ... EDITING: There were two problems with my first tests. Now it works!
In the short time, I'm going to try your suggestion: use a different container format, like MKV, to use as input to the join step. Thanks!
comment:6 by , 11 years ago
It works now!
There were two problems:
1) The function av_compare_streams had an error. It was expecting pointers to streams and it gets passed pointers to pointers to streams (we are sorting an array with pointers, not an array with streams). So, this is the correct code:
int av_compare_streams(const void *st1, const void *st2)
{
return (((*(AVStream **)st1)->id > (*(AVStream **)st2)->id) ? 1 :
((*(AVStream **)st1)->id < (*(AVStream **)st2)->id) ? -1 : 0);
2) The funcion avformat_find_stream_info was invoked from more places than I fixed, so I've made the changes at the end of function avformat_find_stream_info
And now it works great!
comment:7 by , 11 years ago
| Priority: | normal → wish |
|---|---|
| Resolution: | → fixed |
| Status: | open → closed |
I believe this was fixed by Nicolas in 26dea773
comment:8 by , 6 years ago
| Resolution: | fixed |
|---|---|
| Status: | closed → reopened |
Sorry, but I've just tested this now and the problem persists today.
Have a look at stream order shown for this two files:
D:\>ffprobe -i M2U00826.MPG
ffprobe version N-91536-geb94ec3257 Copyright (c) 2007-2018 the FFmpeg developers
built with gcc 7.3.1 (GCC) 20180722
configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
libavutil 56. 18.102 / 56. 18.102
libavcodec 58. 22.100 / 58. 22.100
libavformat 58. 17.101 / 58. 17.101
libavdevice 58. 4.101 / 58. 4.101
libavfilter 7. 26.100 / 7. 26.100
libswscale 5. 2.100 / 5. 2.100
libswresample 3. 2.100 / 3. 2.100
libpostproc 55. 2.100 / 55. 2.100
Input #0, mpeg, from 'M2U00826.MPG':
Duration: 00:00:12.96, start: 0.226767, bitrate: 6674 kb/s
Stream #0:0[0x80]: Audio: ac3, 48000 Hz, stereo, fltp, 256 kb/s
Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, top first), 720x576 [SAR 64:45 DAR 16:9], 25 fps, 25 tbr, 90k tbn, 50 tbc
D:\>ffprobe -i M2U00827.MPG
ffprobe version N-91536-geb94ec3257 Copyright (c) 2007-2018 the FFmpeg developers
built with gcc 7.3.1 (GCC) 20180722
configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
libavutil 56. 18.102 / 56. 18.102
libavcodec 58. 22.100 / 58. 22.100
libavformat 58. 17.101 / 58. 17.101
libavdevice 58. 4.101 / 58. 4.101
libavfilter 7. 26.100 / 7. 26.100
libswscale 5. 2.100 / 5. 2.100
libswresample 3. 2.100 / 3. 2.100
libpostproc 55. 2.100 / 55. 2.100
Input #0, mpeg, from 'M2U00827.MPG':
Duration: 00:02:42.24, start: 0.098722, bitrate: 6319 kb/s
Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, top first), 720x576 [SAR 64:45 DAR 16:9], 25 fps, 25 tbr, 90k tbn, 50 tbc
Stream #0:1[0x80]: Audio: ac3, 48000 Hz, stereo, fltp, 256 kb/s
Both files are comming from the same VideoCam, both are unedited and when I try to concat them with ffmpeg, I get the same errors reported some years ago.
What was the fix applied by Nicolas in 26dea773?
Thanks
comment:9 by , 6 years ago
| Resolution: | → fixed |
|---|---|
| Status: | reopened → closed |
Ok, seen and tested. I leave here some references for anothers interested:
https://ffmpeg.org/ffmpeg-formats.html#Syntax
The muxing of my test files work ok with this "lista.txt":
file M2U00826.MPG stream exact_stream_id 0x1E0 stream exact_stream_id 0x80 file M2U00826.MPG stream exact_stream_id 0x1E0 stream exact_stream_id 0x80
Thanks a lot!
This is currently the expected behaviour (“All files must have the same streams” says the doc; similar streams in different order are not “the same”).
Patches to implement per-file stream mapping are welcome.