title: Can I run ffmpeg from my Python code and return a signal when it's done compressing?
body: <p>Seems that what I am looking for ( a simple ffmpeg interface for python ) is not available for python 3.5. I want to run a commandline from my code that I will fill with variables like : </p>
  
  <pre><code>video_file = "/path/to/video/video.file"
  sound_file = "/path/to/sound/sound.file"
  output_name= (video.file + 'mp4')
  fmpeg -loop 1 -i video_file -i sound_file -c:v libx264 -tune stillimage -c:a aac -strict experimental -b:a 192k -pix_fmt yuv420p -shortest output_name
  </code></pre>
  
  <p>Is it possible to return a signal to trigger the next function that would use output_name as value to do next thing ? Is this even possible ¿?</p>