anchor.diff:      "--enable-adpcmdec"
       "--enable-adpcmenc"
       "--enable-aiff"
  +    "--enable-videoframe_audiolevel"
       "--enable-asfmux"
       "--enable-audiofxbad"
       "--enable-audiomixer"
  
positive.code:     '';
  
    configureFlags = [
      "--enable-option-checking"
      "--disable-maintainer-mode"
      "--enable-nls"
      "--enable-rpath"
      "--disable-fatal-warnings"
      "--disable-debug"
      "--disable-profiling"
      "--disable-valgrind"
  
negative.code:     "--enable-jp2kdecimator"
      "--enable-jpegformat"
      "--enable-librfb"
      "--enable-midi"
      "--enable-mpegdemux"
      "--enable-mpegtsdemux"
  