FFmpeg, when called on a non-video file raises an error

[jcoyne]

I run this command:

      Hydra::FileCharacterization.characterize(f, [:fits, :ffprobe])

This error is raised:

 RuntimeError:
       Unable to execute command "ffprobe -i "/Users/justin/workspace/bawstun/spec/storage/qj/72/pc/13/m/broadway_or_bust.pbcore.xml" -print_format xml -show_streams -v quiet"

It seems like there should be some conditions for which this characterizer is run.

Interestingly ffmpeg is still returning valid output:

<?xml version="1.0" encoding="UTF-8"?>
<ffprobe>
</ffprobe>

but it does warn that: "Invalid data found when processing input"

Perhaps characterizers need to be able to configure whether exit status must be success:
https://github.com/projecthydra/hydra-file_characterization/blob/c5b298f6cbbeac3a708badb43e355e0db40efe7a/lib/hydra/file_characterization/characterizer.rb#L45

[jcoyne]

I'm working around this by doing the following:

def characterize(file)
      out = [] 
      out << Hydra::FileCharacterization.characterize(file, :fits)
      begin
        out << Hydra::FileCharacterization.characterize(file, :ffprobe)
      rescue RuntimeError
        # FFMpeg doesn't exit with success if it's not a format it knows about.
      end
end