Run ffmpeg without outputting configuration information?


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(
    stdin=open(os.devnull, 'rb'),

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
–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?

Asked By: Matt Joiner



Take a look at ffmpeg’s manpage, especially the -loglevel parameter.

Answered By: Dr McKay

AFAIK there is no way, loglevel is no use. Look at ffmpeg.c:


and cmdutils.c:

void show_banner(void)
    fprintf(stderr, "%s version " FFMPEG_VERSION ", Copyright (c) %d-%d the FFmpeg developersn",
            program_name, program_birth_year, this_year);
    fprintf(stderr, "  built on %s %s with %s %sn",
            __DATE__, __TIME__, CC_TYPE, CC_VERSION);
    fprintf(stderr, "  configuration: " FFMPEG_CONFIGURATION "n");
    print_all_libs_info(stderr, INDENT|SHOW_CONFIG);
    print_all_libs_info(stderr, INDENT|SHOW_VERSION);

See here for an unsuccessful attempt of skipping it (I don’t get what the GPL has to do with anything of this). I suggest you to file a bug and hope you are convicing enough.

As many others, I have ffmpeg compiled with show_banner() commented out, it’s simply tiresome.

Answered By: tokland

FFmpeg != Libav

ffmpeg from FFmpeg with -loglevel parameter works as expected.

Answered By: Elvis Presley

This is now possible as of FFmpeg 2.2 with the -hide_banner option. See also the relevant commit and ticket.

Answered By: Andrew Marshall