Dockerfile

# escape=`
#
# Builds FFmpeg on Windows as SHARED libraries (avcodec-61.dll, avformat-61.dll,
# ...) with the MSVC toolchain and packages the headers + import libraries + DLLs
# into zip files that FreeSWITCH's mod_av can download and link, instead of
# compiling the whole of FFmpeg inside the Visual Studio solution.
#
# The compiler is MSVC (cl.exe) throughout. FFmpeg (and x264) have no native
# MSBuild/CMake project -- their only build system is configure+make -- so MSYS2
# bash is installed purely as the POSIX *script driver*. This is exactly how
# vcpkg builds ffmpeg on Windows. Nothing POSIX ends up in the produced
# DLLs/import libs. (openh264 isn't compiled here at all: its import lib +
# headers are derived from Cisco's prebuilt DLL.)
#
# This image only contains the TOOLCHAIN (+ prebuilt openh264/x264 dev libs).
# The actual FFmpeg version is built at `docker run` time from an env var, so a
# new release can be produced without rebuilding the (slow, multi-GB) toolchain.
#
#   Build the toolchain image once:
#     docker build -t ffmpeg-packaging .
#
#   Produce the openh264 (non-GPL) zips for FFmpeg 7.1.5 (writes to .\artifacts):
#     docker run --rm --cpus 8 --memory 16g `
#       -e FFMPEG_VERSION=7.1.5 -e VARIANT=openh264 `
#       -v ${PWD}\artifacts:C:\artifacts `
#       ffmpeg-packaging
#
#   Build from a local source tree instead of downloading:
#     ... -e FFMPEG_SRC=C:\ffmpeg-src -v ${PWD}\ffmpeg-7.1.5:C:\ffmpeg-src ...
#
# Requires Windows containers. With Docker Desktop's default hyperv isolation
# any base image build works; otherwise the host must be equal-or-newer than the
# base image for process isolation.

ARG WINDOWS_BASE=mcr.microsoft.com/windows/servercore:ltsc2025
FROM ${WINDOWS_BASE}

ARG VS_BOOTSTRAPPER_URL=https://aka.ms/vs/17/release/vs_buildtools.exe

SHELL ["powershell", "-NoLogo", "-NoProfile", "-ExecutionPolicy", "Bypass", "-Command", "$ErrorActionPreference='Stop'; $ProgressPreference='SilentlyContinue';"]

# ---------------------------------------------------------------------------
# 1. Chocolatey + non-VS prerequisites:
#    - git    : clone openh264/x264 (and optionally ffmpeg) sources
#    - nasm   : x86 assembler for ffmpeg/openh264/x264 (on PATH for cl)
#    - msys2  : the POSIX shell that drives configure/make (NOT a compiler)
#    - 7zip   : decompress Cisco's prebuilt openh264 .dll.bz2
# ---------------------------------------------------------------------------
RUN [System.Net.ServicePointManager]::SecurityProtocol = [System.Net.SecurityProtocolType]::Tls12; `
    Invoke-Expression ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))

RUN choco install -y --no-progress git nasm 7zip msys2; `
    if ($LASTEXITCODE -ne 0) { throw "choco install failed ($LASTEXITCODE)" }

# ---------------------------------------------------------------------------
# 2. Visual Studio 2022 Build Tools: C++ workload (MSVC v143 + Windows SDK).
#    Exit code 3010 == success-but-reboot-required, fine in an image.
# ---------------------------------------------------------------------------
RUN Invoke-WebRequest -Uri $env:VS_BOOTSTRAPPER_URL -OutFile C:\vs_buildtools.exe; `
    Write-Host 'Installing Visual Studio Build Tools (this takes a while)...'; `
    $p = Start-Process -FilePath C:\vs_buildtools.exe -Wait -PassThru -ArgumentList `
        '--quiet','--wait','--norestart','--nocache', `
        '--installPath','C:\BuildTools', `
        '--add','Microsoft.VisualStudio.Workload.VCTools', `
        '--includeRecommended'; `
    if ($p.ExitCode -ne 0 -and $p.ExitCode -ne 3010) { throw "VS Build Tools install failed ($($p.ExitCode))" }; `
    Remove-Item C:\vs_buildtools.exe -Force

# ---------------------------------------------------------------------------
# 3. MSYS2 packages needed to *drive* the builds: make + automake (ar-lib) +
#    pkgconf (for --enable-libopenh264 detection) + diffutils + tar/xz.
#    These are POSIX build tooling, not compilers.
# ---------------------------------------------------------------------------
RUN $bash = 'C:\tools\msys64\usr\bin\bash.exe'; `
    & $bash -lc 'pacman -Sy --noconfirm'; `
    & $bash -lc 'pacman -S --noconfirm --needed make automake diffutils pkgconf tar xz'; `
    if ($LASTEXITCODE -ne 0) { throw "pacman package install failed ($LASTEXITCODE)" }

# ---------------------------------------------------------------------------
# 4. Codec dev libs into C:\deps: openh264 (import lib + wels headers derived
#    from Cisco's prebuilt DLL) and x264 (built from source as a shared DLL).
#    avcodec imports both at runtime. openh264 is required (non-GPL variant);
#    x264 is best-effort (GPL variant).
# ---------------------------------------------------------------------------
# OPENH264_VERSION must match the openh264.dll FreeSWITCH downloads at runtime
# (stack w32\download_openh264.props + Setup.CA.DownloadOpenH264 == 1.8.0), since
# ffmpeg's libopenh264 wrapper is version-gated against the wels headers.
ENV DEPS_PREFIX=C:\deps `
    MSYS2_ROOT=C:\tools\msys64 `
    OPENH264_VERSION=1.8.0 `
    X264_BRANCH=stable

COPY build-deps.ps1 C:\build-deps.ps1
RUN C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe -NoLogo -NoProfile -ExecutionPolicy Bypass `
        -File C:\build-deps.ps1 -Deps 'openh264 x264'

# ---------------------------------------------------------------------------
# 5. Build driver + runtime defaults. Override any with `docker run -e ...`.
# ---------------------------------------------------------------------------
COPY build-ffmpeg.ps1 C:\build-ffmpeg.ps1
# Cisco openh264 binary-license notice, bundled into the openh264 zip by
# build-ffmpeg.ps1 (it looks for this next to the script, i.e. C:\ in the image).
COPY OPENH264_BINARY_LICENSE.txt C:\OPENH264_BINARY_LICENSE.txt

ENV FFMPEG_VERSION=7.1.5 `
    CONFIGS="Release Debug" `
    ARCH=x64 `
    VARIANT=openh264 `
    PKG_PREFIX=ffmpeg `
    OUT_DIR=C:\artifacts

ENTRYPOINT ["C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe", "-NoLogo", "-NoProfile", "-ExecutionPolicy", "Bypass", "-File", "C:\\build-ffmpeg.ps1"]