use pre-compiled deb to avoid non-free drivers

Dockerfile

@@ -1,5 +1,4 @@
 ARG DOTNET_VERSION=3.1
-ARG FFMPEG_VERSION=latest
 
 FROM node:alpine as web-builder
 ARG JELLYFIN_WEB_VERSION=master
@@ -17,7 +16,6 @@ ENV DOTNET_CLI_TELEMETRY_OPTOUT=1
 # see https://success.docker.com/article/how-to-reserve-resource-temporarily-unavailable-errors-due-to-tasksmax-setting
 RUN dotnet publish Jellyfin.Server --disable-parallel --configuration Release --output="/jellyfin" --self-contained --runtime linux-x64 "-p:GenerateDocumentationFile=false;DebugSymbols=false;DebugType=none"
 
-FROM jellyfin/ffmpeg:${FFMPEG_VERSION} as ffmpeg
 FROM debian:buster-slim
 
 # https://askubuntu.com/questions/972516/debian-frontend-environment-variable
@@ -27,32 +25,26 @@ ARG APT_KEY_DONT_WARN_ON_DANGEROUS_USAGE=DontWarn
 # https://github.com/NVIDIA/nvidia-docker/wiki/Installation-(Native-GPU-Support)
 ENV NVIDIA_DRIVER_CAPABILITIES="compute,video,utility"
 
-COPY --from=ffmpeg /opt/ffmpeg /opt/ffmpeg
 COPY --from=builder /jellyfin /jellyfin
 COPY --from=web-builder /dist /jellyfin/jellyfin-web
 # Install dependencies:
-#   libfontconfig1: needed for Skia
-#   libgomp1: needed for ffmpeg
-#   libva-drm2: needed for ffmpeg
-#   mesa-va-drivers: needed for VAAPI
+#   mesa-va-drivers: needed for AMD VAAPI
 RUN apt-get update \
+ && apt-get install --no-install-recommends --no-install-suggests -y ca-certificates gnupg wget apt-transport-https \
+ && wget -O - https://repo.jellyfin.org/jellyfin_team.gpg.key | sudo apt-key add - \
+ && echo "deb [arch=$( dpkg --print-architecture )] https://repo.jellyfin.org/$( awk -F'=' '/^ID=/{ print $NF }' /etc/os-release ) $( awk -F'=' '/^VERSION_CODENAME=/{ print $NF }' /etc/os-release ) main" | sudo tee /etc/apt/sources.list.d/jellyfin.list \
+ && apt-get update \
  && apt-get install --no-install-recommends --no-install-suggests -y \
-   libfontconfig1 \
-   libgomp1 \
-   libva-drm2 \
    mesa-va-drivers \
+   jellyfin-ffmpeg \
    openssl \
-   ca-certificates \
-   vainfo \
-   i965-va-driver \
    locales \
- && apt-get clean autoclean -y\
- && apt-get autoremove -y\
+ && apt-get remove gnupg wget apt-transport-https -y \
+ && apt-get clean autoclean -y \
+ && apt-get autoremove -y \
  && rm -rf /var/lib/apt/lists/* \
  && mkdir -p /cache /config /media \
  && chmod 777 /cache /config /media \
- && ln -s /opt/ffmpeg/bin/ffmpeg /usr/local/bin \
- && ln -s /opt/ffmpeg/bin/ffprobe /usr/local/bin \
  && sed -i -e 's/# en_US.UTF-8 UTF-8/en_US.UTF-8 UTF-8/' /etc/locale.gen && locale-gen
 
 ENV DOTNET_SYSTEM_GLOBALIZATION_INVARIANT=1
@@ -65,4 +57,4 @@ VOLUME /cache /config /media
 ENTRYPOINT ["./jellyfin/jellyfin", \
     "--datadir", "/config", \
     "--cachedir", "/cache", \
-    "--ffmpeg", "/usr/local/bin/ffmpeg"]
+    "--ffmpeg", "/usr/lib/jellyfin-ffmpeg/ffmpeg"]