[FFmpeg-user] -t option is ignored

Martin G ebisumartin at gmail.com
Wed Mar 28 10:31:16 CEST 2012


I tried moving the time specs to the beginning of the command like so:

ffmpeg -ss 01:05:16 -t 120 -i input.avi -vcodec copy -acodec copy output.avi

... however this hasn't changed anything. Instead of 120 seconds
worth, I get over 45 minutes.

If -vcodec copy and -acodec copy "don't play well" with -t, then what
should I use instead to preserve the same quality of video in the sub
clip?

Here is the output:

f$ ffmpeg -ss 01:05:16 -t 120 -i input.avi -vcodec copy -acodec copy output.avi
ffmpeg version 0.7.3-4:0.7.3-0ubuntu0.11.10.1, Copyright (c) 2000-2011
the Libav developers
  built on Jan  4 2012 16:08:51 with gcc 4.6.1
  configuration: --extra-version='4:0.7.3-0ubuntu0.11.10.1'
--arch=amd64 --prefix=/usr --enable-vdpau --enable-bzlib
--enable-libgsm --enable-libschroedinger --enable-libspeex
--enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib
--enable-libvpx --enable-runtime-cpudetect --enable-vaapi --enable-gpl
--enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394
--enable-shared --disable-static
  WARNING: library configuration mismatch
  avutil      configuration: --extra-version='4:0.7.3ubuntu0.11.10.1'
--arch=amd64 --prefix=/usr --enable-vdpau --enable-bzlib
--enable-libgsm --enable-libschroedinger --enable-libspeex
--enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib
--enable-libvpx --enable-runtime-cpudetect --enable-vaapi
--enable-libopenjpeg --enable-gpl --enable-postproc --enable-swscale
--enable-x11grab --enable-libdirac --enable-libmp3lame
--enable-librtmp --enable-libx264 --enable-libxvid
--enable-libvo-aacenc --enable-version3 --enable-libvo-amrwbenc
--enable-version3 --enable-libdc1394 --enable-shared --disable-static
  avcodec     configuration: --extra-version='4:0.7.3ubuntu0.11.10.1'
--arch=amd64 --prefix=/usr --enable-vdpau --enable-bzlib
--enable-libgsm --enable-libschroedinger --enable-libspeex
--enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib
--enable-libvpx --enable-runtime-cpudetect --enable-vaapi
--enable-libopenjpeg --enable-gpl --enable-postproc --enable-swscale
--enable-x11grab --enable-libdirac --enable-libmp3lame
--enable-librtmp --enable-libx264 --enable-libxvid
--enable-libvo-aacenc --enable-version3 --enable-libvo-amrwbenc
--enable-version3 --enable-libdc1394 --enable-shared --disable-static
  libavutil    51.  7. 0 / 51.  7. 0
  libavcodec   53.  6. 0 / 53.  6. 0
  libavformat  53.  3. 0 / 53.  3. 0
  libavdevice  53.  0. 0 / 53.  0. 0
  libavfilter   2.  4. 0 /  2.  4. 0
  libswscale    2.  0. 0 /  2.  0. 0
  libpostproc  52.  0. 0 / 52.  0. 0
[mpeg4 @ 0x1f67540] Invalid and inefficient vfw-avi packed B frames detected

Seems stream 0 codec frame rate differs from container frame rate:
30000.00 (30000/1) -> 23.98 (24000/1001)
Input #0, avi, from 'input.avi':
  Metadata:
    title           : Triumph Des Willens
    comment         : Ripped by Reevel
    encoder         : VirtualDubMod 1.4.13
  Duration: 01:50:30.50, start: 0.000000, bitrate: 886 kb/s
    Stream #0.0: Video: mpeg4, yuv420p, 512x400 [PAR 1:1 DAR 32:25],
23.98 fps, 23.98 tbr, 23.98 tbn, 30k tbc
    Stream #0.1: Audio: mp3, 44100 Hz, mono, s16, 93 kb/s
Output #0, avi, to 'output.avi':
  Metadata:
    INAM            : Triumph Des Willens
    ILNG            : Undefined
    ICMT            : Ripped by Reevel
    ISFT            : Lavf53.3.0
    Stream #0.0: Video: mpeg4, yuv420p, 512x400 [PAR 1:1 DAR 32:25],
q=2-31, 23.98 tbn, 23.98 tbc
    Stream #0.1: Audio: libmp3lame, 44100 Hz, mono, 93 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
  Stream #0.1 -> #0.1
Press ctrl-c to stop encoding
[NULL @ 0x1f67540] Invalid and inefficient vfw-avi packed B frames detected
frame= 5057 fps=4915 q=-1.0 size=   13866kB time=120.01 bitrate=
946.5kbits/s   frame= 8317 fps=5456 q=-1.0 size=   13866kB time=120.01
bitrate= 946.5kbits/s   frame=15897 fps=7796 q=-1.0 size=   13866kB
time=120.01 bitrate= 946.5kbits/s   frame=19543 fps=7651 q=-1.0 size=
 13866kB time=120.01 bitrate= 946.5kbits/s   frame=22683 fps=7426
q=-1.0 size=   13866kB time=120.01 bitrate= 946.5kbits/s   frame=29647
fps=8338 q=-1.0 size=   13866kB time=120.01 bitrate= 946.5kbits/s
frame=33261 fps=8199 q=-1.0 size=   13866kB time=120.01 bitrate=
946.5kbits/s   frame=37141 fps=8150 q=-1.0 size=   13866kB time=120.01
bitrate= 946.5kbits/s   frame=40029 fps=7915 q=-1.0 size=   13866kB
time=120.01 bitrate= 946.5kbits/s   frame=44628 fps=8016 q=-1.0 size=
 13866kB time=120.01 bitrate= 946.5kbits/s   frame=47354 fps=7766
q=-1.0 size=   13866kB time=120.01 bitrate= 946.5kbits/s   frame=51237
fps=7765 q=-1.0 size=   13866kB time=120.01 bitrate= 946.5kbits/s
frame=56325 fps=7934 q=-1.0 size=   13866kB time=120.01 bitrate=
946.5kbits/s   frame=61463 fps=8087 q=-1.0 size=   13866kB time=120.01
bitrate= 946.5kbits/s   frame=65294 fps=4227 q=-1.0 Lsize=  301685kB
time=120.01 bitrate=20593.9kbits/s
video:298534kB audio:1474kB global headers:0kB muxing overhead 0.558787%


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