anchor.diff:      php7-phar \
       pkgconf \
       pkgconfig \
  -#    rtmpdump \
  -#    rtmpdump-dev \
       tar \
       wget \
  -#    x264-dev \
  -#    x265-dev \
       yasm \
       yasm-dev \
       zlib-dev \
  
positive.code:     libogg-dev \
      libtheora \
      libtheora-dev \
  #    libvpx \
  #    libvpx-dev \
      libvorbis \
      libvorbis-dev \
  #    libwebp \
  #    libwebp-dev \
      nasm \
      openssl \
      openssl-dev \
  
negative.code:   --enable-gpl \
    --enable-nonfree \
    --enable-small \
    --enable-libmp3lame \
    --enable-libtheora \
    --enable-libvorbis \
    --enable-libopus \
    --enable-libfdk_aac \
    --enable-avresample \
    --enable-libfreetype \
    --enable-openssl \
  