anchor.diff: -FROM debian AS build
  +FROM ubuntu:20.04 AS build
   
   ARG NUM_CORES=2
   
   ENV \
   	PREFIX="/tmp/ffmpeg_build" \
  -	PKG_CONFIG_PATH="/tmp/ffmpeg_build/lib/pkgconfig"
  +	DEBIAN_FRONTEND=noninteractive
   
   # Dependencies
  -RUN apt-get update -qq \
  +RUN apt-get update \
   	&& apt-get -y install \
   		autoconf \
   		automake \
   		build-essential \
   		cmake \
  +		fontconfig \
  +		frei0r-plugins-dev \
   		git \
  +		git-core \
   		libass-dev \
  +		libfdk-aac-dev \
  +		libfontconfig1-dev \
   		libfreetype6-dev \
  +		libfribidi-dev \
  +		libgnutls28-dev \
  +		libmp3lame-dev \
  +		libnuma-dev \
  +		libopencore-amrnb-dev \
  +		libopencore-amrwb-dev \
  +		libopus-dev \
   		libsdl2-dev \
  +		libspeex-dev \
   		libtheora-dev \
   		libtool \
   		libva-dev \
   		libvdpau-dev \
  +		libvo-amrwbenc-dev \
   		libvorbis-dev \
  -		libxcb1-dev \
  +		libvpx-dev \
  +		libwebp-dev \
  +		libx264-dev \
  +		libx265-dev \
   		libxcb-shm0-dev \
   		libxcb-xfixes0-dev \
  +		libxcb1-dev \
  +		libxvidcore-dev \
   		mercurial \
  +		meson \
  +		ninja-build \
   		pkg-config \
   		texinfo \
   		wget \
  +		yasm \
   		zlib1g-dev \
  -		fontconfig \
  -		frei0r-plugins-dev \
  -		libass-dev \
  -		libfontconfig1-dev \
  -		libmp3lame-dev \
  -		libopencore-amrnb-dev \
  -		libopencore-amrwb-dev \
  -		libopus-dev \
  -		libspeex-dev \
  -		libtheora-dev \
  -		libvorbis-dev \
  -		libvo-amrwbenc-dev \
  -		libwebp-dev \
  -		libx264-dev \
  -		libnuma-dev \
  -		libvpx-dev \
  -		libxvidcore-dev \
  -		texinfo \
  -		yasm \
   	&& apt-get clean \
   	&& apt-get autoremove -y \
   	&& rm -rf /var/lib/apt/lists/*
  
positive.code: 		--disable-debug \
  		--disable-runtime-cpudetect \
  		--disable-ffplay \
  		--disable-ffserver \
  		--disable-doc \
  		--disable-network \
  		--disable-devices \
  
negative.code: 	&& make clean
  
  # FFmpeg
  RUN git clone https://github.com/ffmpeg/ffmpeg.git --branch master --single-branch
  RUN export \
  		BIN_DIR="/opt/ffmpeg/bin" \
  		PATH="${BIN_DIR}:${PATH}" \
  	&& cd ./ffmpeg \
  	&& ./configure \
  		--cc=gcc \
  		--prefix="${PREFIX}" \
  		--pkg-config="pkg-config --static" \
  		--extra-cflags="-I${PREFIX}/include -static" \
  		--extra-ldflags="-L${PREFIX}/lib -static" \
  		--extra-libs="-lpthread -lm" \
  