anchor.diff:  
       "-Ddts=disabled" # required `libdca` library not packaged in nixpkgs as of writing, and marked as "BIG FAT WARNING: libdca is still in early development"
       "-Dfaac=${if faacSupport then "enabled" else "disabled"}"
  -    "-Dgsm=disabled" # as of writing, with `gsm` in `buildInputs` we get "GSM plugin is enabled: found libgsm but no headers"; gsm packaging problem?
       "-Diqa=disabled" # required `dssim` library not packaging in nixpkgs as of writing
       "-Dmsdk=disabled" # not packaged in nixpkgs as of writing / no Windows support
       # As of writing, with `libmpcdec` in `buildInputs` we get
  
positive.code:     directfb
      fdk_aac
      flite
      libaom
      libdc1394
      libde265
  
negative.code: , directfb
  , fdk_aac
  , flite
  , gsm
  , libaom
  , libdc1394
  , libde265
  