CI ARM: build own FFmpeg with OMX fix

This fixes a problem when the H.264 stream includes PPS/SPS only at the
beginning which effectively makes it unusable with UltraGrid.

.github/scripts/Linux/arm/bootstrap.sh

@@ -2,11 +2,24 @@
 
 # If changing the file, do not forget to regenerate cache in ARM Build GitHub action
 
+ARCH=$1
 BUILD_DIR=$2
 
 sudo chroot $BUILD_DIR /bin/sh -c 'if grep -q Raspbian /etc/os-release; then sed -i s-http://deb.debian.org/debian-http://mirrordirector.raspbian.org/raspbian/- /etc/apt/sources.list && apt-get -y update; fi' # https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/1670905 workaround
-sudo chroot $BUILD_DIR /bin/sh -c 'apt-get -y install build-essential pkg-config autoconf automake libtool'
-sudo chroot $BUILD_DIR /bin/sh -c 'apt-get -y install portaudio19-dev libsdl2-dev libglib2.0-dev libglew-dev libcurl4-openssl-dev freeglut3-dev libssl-dev libjack-dev libavcodec-dev libavformat-dev libswscale-dev libasound2-dev'
+sudo chroot $BUILD_DIR /bin/sh -c 'apt-get -y install build-essential git pkg-config autoconf automake libtool'
+sudo chroot $BUILD_DIR /bin/sh -c 'apt-get -y install portaudio19-dev libsdl2-dev libglib2.0-dev libglew-dev libcurl4-openssl-dev freeglut3-dev libssl-dev libjack-dev libasound2-dev'
+if [ $ARCH = armhf ]; then # Raspbian - build own FFmpeg with OMX camera patch
+        sudo chroot $BUILD_DIR /bin/sh -c "git clone --depth 1 https://github.com/raspberrypi/firmware.git firmware && mv firmware/* / && echo /opt/vc/lib > /etc/ld.so.conf.d/00-vmcs.conf && ldconfig"\
+"sed -i '/^deb /p;s/deb/deb-src/' /etc/apt/sources.list "\
+"&& apt-get -y update && apt-get -y build-dep ffmpeg"\
+"&& apt-get -y remove libavcodec58 && apt-get -y autoremove"\
+"&& git clone --depth 1 https://github.com/FFmpeg/FFmpeg.git && cd FFmpeg"\
+"&& git fetch --depth 2 https://github.com/Serveurperso/FFmpeg.git && git cherry-pick FETCH_HEAD"\
+"&& ./configure --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-neon --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-frei0r --enable-libx264 --enable-mmal --enable-omx-rpi --cpu=arm1176jzf-s --enable-shared --disable-static && make -j 3 && make install"\
+"&& cd && rm -rf FFmpeg"
+else
+        sudo chroot $BUILD_DIR /bin/sh -c 'apt-get -y install libavcodec-dev libavformat-dev libswscale-dev'
+fi
 sudo chroot $BUILD_DIR /bin/sh -c 'apt-get -y install desktop-file-utils git-core libfuse-dev libcairo2-dev cmake wget zsync' # to build appimagetool
 sudo chroot $BUILD_DIR /bin/sh -c 'git clone https://github.com/AppImage/AppImageKit.git && cd AppImageKit && ./build.sh && cd build && cmake -DAUXILIARY_FILES_DESTINATION= .. && make install'
 sudo chroot $BUILD_DIR /bin/sh -c 'rm -rf AppImageKit; apt-get -y clean'

.github/workflows/arm-build.yml

@@ -30,7 +30,7 @@ jobs:
       uses: actions/cache@v2
       with:
         path: 'chroot.tar'
-        key: cache-bootstrap-${{ matrix.arch }}-3
+        key: cache-bootstrap-${{ matrix.arch }}-4
     - name: Debootstrap
       if: steps.cache-bootstrap.outputs.cache-hit != 'true'
       run: |