I'm invoking ffmpeg
with subprocess.Popen
, and trying to capture the stderr
output and write it to logging
.
args = ['ffmpeg', '-i', path]
if start:
args += ['-ss', start]
if end:
args += ['-t', end]
args += [
'-vcodec', 'copy',
'-acodec', 'copy',
'-scodec', 'copy',
'-f', 'mpegts',
'-y', '/dev/stdout']
self.child = subprocess.Popen(
args,
stdin=open(os.devnull, 'rb'),
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
ffmpeg
generates a lot of configuration information like the following:
FFmpeg version 0.6.2-4:0.6.2-1ubuntu1, Copyright (c) 2000-2010 the Libav developers built on Mar 22 2011 15:55:04 with gcc 4.5.2
configuration: --extra-version=4:0.6.2-1ubuntu1 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libgsm --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libdc1394 --enable-shared --disable-static WARNING: library configuration mismatch libavutil configuration: --extra-version=4:0.6.2-1ubuntu2 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libdirac --enable-libgsm --enable-libopenjpeg --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-libopenjpeg --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libfaad --enable-libdirac --enable-libfaad --enable-libmp3lame --enable-librtmp --enable-libx264 --enable-libxvid --enable-libdc1394 --enable-shared --disable-static libavcodec configuration: --extra-version=4:0.6.2-1ubuntu2 --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libdirac --enable-libgsm --enable-libopenjpeg --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --enable-libvpx --disable-stripping --enable-runtime-cpudetect --enable-vaapi --enable-libopenjpeg --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libfaad --enable-libdirac --enable-libfaad --enable-libmp3lame --enable-librtmp --enable-libx264 --enable-libxvid --enable-libdc1394 --enable-shared --disable-static libavutil 50.15. 1 / 50.15. 1
libavcodec 52.72. 2 / 52.72. 2
libavformat 52.64. 2 / 52.64. 2
libavdevice 52. 2. 0 / 52. 2. 0
libavfilter 1.19. 0 / 1.19. 0
libswscale 0.11. 0 / 0.11. 0
libpostproc 51. 2. 0 / 51. 2. 0
Prior to finally outputting the stuff I'd like to log:
Seems stream 0 codec frame rate differs from container frame rate: 47.95 (66893/1395) -> 23.98 (66893/2790) At least one output file must be specified
Is there an option to prevent this excessive output? Should I be doing it differently?
This is now possible as of FFmpeg 2.2 with the -hide_banner
option. See also the relevant commit and ticket.