anchor.diff:   *
    * Not packaged:
    *   aacplus avisynth cdio-paranoia crystalhd libavc1394 libiec61883
  - *   libmxf libnut libquvi nvenc opencl opencore-amr openh264 oss shine twolame
  + *   libmxf libnut libquvi nvenc opencl openh264 oss shine twolame
    *   utvideo vo-aacenc vo-amrwbenc xvmc zvbi blackmagic-design-desktop-video
    *
    * Need fixes to support Darwin:
  
positive.code:     (enableFeature nvenc "nvenc")
      (enableFeature (openal != null) "openal")
      #(enableFeature opencl "opencl")
      #(enableFeature (opencore-amr != null && version3Licensing) "libopencore-amrnb")
      #(enableFeature (opencv != null) "libopencv")
      (enableFeature openglExtlib "opengl")
      #(enableFeature (openh264 != null) "openh264")
  
negative.code: , nvenc ? false, nvidia-video-sdk ? null # NVIDIA NVENC support
  , openal ? null # OpenAL 1.1 capture support
  #, opencl ? null # OpenCL code
  , opencore-amr ? null # AMR-NB de/encoder & AMR-WB decoder
  #, opencv ? null # Video filtering
  , openglExtlib ? false, mesa ? null # OpenGL rendering
  #, openh264 ? null # H.264/AVC encoder
  