title: Check for album art with mutagen
body: <p>I used eyed3 to work with <code>id3</code> but everytime I want to load a file with a special character like <code>"ü"</code> it crashes because it cannot open these files...</p>
  
  <p>That's why I switched to mutagen. I want check my whole library for album art. </p>
  
  <pre><code>#pict_test function
  
  def pict_test(filepath):
      audio = File( filepath )
  
      if 'covr' in audio or 'APIC:' in audio:
          return True
  
      return False
  
  #main
  filepath = "/home/jds/Desktop/M_M/"
  
  #get all files in this directory including sub directories
  files = getFiles.get_all_files( filepath ) 
  files = getMp3Files( files )
  
  print "%d mp3 files found.\n" % ( len(files) )
  f = open( "No Img.txt", "w" )
  for f in files:
      if not pict_test( f ): #if no image is found write filepath to file
          f.write( f + "\n" )
  f.close()
  </code></pre>
  
  <p>This "works". I get files <strong>without</strong> album art BUT also files <strong>with</strong> album art. </p>
  
  <p>What is wrong?</p>