anchor.diff:    --enable-gpl \
     --enable-nonfree \
     --enable-small \
  +# audio: mp3 codec
     --enable-libmp3lame \
  -  --enable-libx264 \
  -  --enable-libx265 \
  -  --enable-libvpx \
  +# video: h264 codec
  +#  --enable-libx264 \
  +# video: h265 codec
  +#  --enable-libx265 \
  +# video: vp9 codec
  +#  --enable-libvpx \
     --enable-libtheora \
  +# audio: ogg vorbis codec
     --enable-libvorbis \
  +# audio: opus codec
     --enable-libopus \
  +# audio: aac codec (high quality, nonfree)
     --enable-libfdk_aac \
  -  --enable-libass \
  -  --enable-libwebp \
  -  --enable-librtmp \
  -  --enable-postproc \
  +#  video: subtitle renderer
  +#  --enable-libass \
  +# image: webp format support
  +#  --enable-libwebp \
  +# streaming: RTPM streaming protocol
  +#  --enable-librtmp \
  +# video: postprocessing
  +#  --enable-postproc \
  +
  +# audio: resampling
     --enable-avresample \
     --enable-libfreetype \
     --enable-openssl \
  
positive.code:     php7-phar \
      pkgconf \
      pkgconfig \
      rtmpdump \
      rtmpdump-dev \
      tar \
      wget \
      x264-dev \
      x265-dev \
      yasm \
      yasm-dev \
      zlib-dev \
  
negative.code: RUN cd /tmp/ \
     && wget https://github.com/nkari82/mp4v2/archive/master.zip \
     && unzip master.zip \
     && rm master.zip \
     && cd mp4v2-master \
     && ./configure && make && make install && make distclean && rm -rf /tmp/*
  
  RUN cd /tmp/ \
     && wget https://github.com/nu774/fdkaac/archive/1.0.0.tar.gz \
     && tar xzf 1.0.0.tar.gz \
     && rm 1.0.0.tar.gz \
     && cd fdkaac-1.0.0 \
     && autoreconf -i && ./configure && make && make install && rm -rf /tmp/*
  
  RUN wget https://github.com/sandreas/m4b-tool/releases/download/v.${M4B_TOOL_VERSION}/m4b-tool.phar -O /usr/local/bin/m4b-tool \
      && chmod +x /usr/local/bin/m4b-tool
  
  CMD ["/bin/sh"]
  