[FFmpeg-trac] #3108(FFmpeg:new): concat demuxer doesn't work right

[FFmpeg]

#3108: concat demuxer doesn't work right
--------------------------------+----------------------------------
             Reporter:  Xtophe  |                     Type:  defect
               Status:  new     |                 Priority:  normal
            Component:  FFmpeg  |                  Version:  2.1
             Keywords:          |               Blocked By:
             Blocking:          |  Reproduced by developer:  0
Analyzed by developer:  0       |
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 The concat demuxer does not work correct. It creates a valid playable file
 but all files in the concat file are not added. Just the first file is
 copied.

 Example:
 A simple example to concat two small files (in the case two of the same
 files but it also does not work when you use different sources).

 The used concatfile.txt :

 file /Users/imac/Desktop/10secMov.mov
 file /Users/imac/Desktop/10secMov.mov

 The used FFmpeg command line:

 ffmpeg -f concat -i /Users/imac/Desktop/concatfile.txt -codec copy -y
 /Users/imac/Desktop/Sample_Merged.mov


 ffmpeg output:

 ffmpeg version 2.1 Copyright (c) 2000-2013 the FFmpeg developers
   built on Aug  1 2013 16:03:22 with llvm-gcc 4.2.1 (LLVM build
 2336.11.00)
   configuration: --prefix=/Volumes/tempdisk/sw --as=yasm --enable-gpl
 --enable-pthreads --disable-ffplay --disable-ffserver --disable-shared
 --enable-static --enable-libvpx --disable-decoder=libvpx --enable-
 libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis
 --enable-libx264 --enable-libxvid --enable-zlib --enable-avfilter
 --enable-fontconfig --enable-libfreetype --enable-libass --enable-
 libutvideo --enable-filters --enable-postproc --enable-runtime-cpudetect
   libavutil      52. 38.100 / 52. 38.100
   libavcodec     55. 18.102 / 55. 18.102
   libavformat    55. 12.100 / 55. 12.100
   libavdevice    55.  3.100 / 55.  3.100
   libavfilter     3. 79.101 /  3. 79.101
   libswscale      2.  3.100 /  2.  3.100
   libswresample   0. 17.102 /  0. 17.102
   libpostproc    52.  3.100 / 52.  3.100
 [concat @ 0x7fe280818600] Estimating duration from bitrate, this may be
 inaccurate
 Input #0, concat, from '/Users/imac/Desktop/concatfile.txt':
   Duration: 00:00:00.02, start: 0.000000, bitrate: 26 kb/s
     Stream #0:0: Video: h264 (High) (avc1 / 0x31637661), yuv420p, 480x270
 [SAR 1:1 DAR 16:9], 976 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc
     Stream #0:1: Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, fltp,
 131 kb/s
 Output #0, mov, to '/Users/imac/Desktop/Sample_Merged.mov':
   Metadata:
     encoder         : Lavf55.12.100
     Stream #0:0: Video: h264 (avc1 / 0x31637661), yuv420p, 480x270 [SAR
 1:1 DAR 16:9], q=2-31, 976 kb/s, 25 fps, 12800 tbn, 12800 tbc
     Stream #0:1: Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, 131
 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (copy)
   Stream #0:1 -> #0:1 (copy)
 Press [q] to stop, [?] for help
 frame=  250 fps=0.0 q=-1.0 Lsize=    1361kB time=00:00:10.03
 bitrate=1111.3kbits/s
 video:1191kB audio:160kB subtitle:0 global headers:0kB muxing overhead
 0.666447%


 The resulting sample_merged.mov file is working BUT:

 - It has the file size of the first file (10secMov.mov)
 - The movie length is also the same as the first file (10secMov.mov)

 Basically this means the concat hasn't been done. It just copied the video
 and audio streams of the first file.

 BTW this also happens with the latest GIT version.

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/3108>
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