Hide ffmpeg output when capturing stream.

[fergie4000]

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---

I'll start by saying I'm no expert with Python so I've probably overlooked something simple. I'm using youtube-dl as a module to capture Chaturbate streams and no matter what I do I can't stop ffmpeg output being shown in the terminal. Have included the code I'm trying for now.

from __future__ import unicode_literals
import os, sys

# These print
print('test out')
sys.stderr.write('test error\n')

# Redirect output to null
f = open(os.devnull, 'w')
sys.stdout = f
sys.stderr = f

from youtube_dl import YoutubeDL

# These don't print
print('another test out')
sys.stderr.write('another test error\n')

options = {
}

url = 'https://chaturbate.com/sexydea/'
with YoutubeDL(options) as ydl:
    ydl.download([url])

This produces the following output.

$ python pstest.py 
test out
test error
ffmpeg version 2.8.6-1ubuntu2 Copyright (c) 2000-2016 the FFmpeg developers
  built with gcc 5.3.1 (Ubuntu 5.3.1-11ubuntu1) 20160311
  configuration: --prefix=/usr --extra-version=1ubuntu2 --build-suffix=-ffmpeg --toolchain=hardened --libdir=/usr/lib/i386-linux-gnu --incdir=/usr/include/i386-linux-gnu --cc=cc --cxx=g++ --enable-gpl --enable-shared --disable-stripping --disable-decoder=libopenjpeg --disable-decoder=libschroedinger --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxvid --enable-libzvbi --enable-openal --enable-opengl --enable-x11grab --enable-libdc1394 --enable-libiec61883 --enable-libzmq --enable-frei0r --enable-libx264 --enable-libopencv --disable-i686
  libavutil      54. 31.100 / 54. 31.100
  libavcodec     56. 60.100 / 56. 60.100
  libavformat    56. 40.101 / 56. 40.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 40.101 /  5. 40.101
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.101 /  1.  2.101
  libpostproc    53.  3.100 / 53.  3.100

  ...etc

Any ideas what I'm missing?

[yan12125]

ffmpeg's output is not controller by the process running youtube-dl. Python in this case. You can add 'postprocessor_args': ['-loglevel', 'panic'] to options.
Another approach is requested (but not implemented yet) in #8571: suppress ffmpeg outputs if 'quiet': True is specified in options.

[fergie4000]

I ended up needing external_downloader_args instead, but thanks a lot for pointing me in the right direction.