ExoPlayer FFmpeg extension

The FFmpeg extension provides FfmpegAudioRenderer, which uses FFmpeg for decoding and can render audio encoded in a variety of formats.

License note

Please note that whilst the code in this repository is licensed under Apache 2.0, using this extension also requires building and including one or more external libraries as described below. These are licensed separately.

Build instructions

To use this extension you need to clone the ExoPlayer repository and depend on its modules locally. Instructions for doing this can be found in ExoPlayer's top level README. The extension is not provided via JCenter (see #2781 for more information).

In addition, it's necessary to build the extension's native components as follows:

• Set the following environment variables:

cd "<path to exoplayer checkout>"
FFMPEG_EXT_PATH="$(pwd)/extensions/ffmpeg/src/main/jni"

• Download the Android NDK and set its location in an environment variable. Only versions up to NDK 15c are supported currently.

NDK_PATH="<path to Android NDK>"

• Set up host platform ("darwin-x86_64" for Mac OS X):

HOST_PLATFORM="linux-x86_64"

• Fetch and build FFmpeg. The configuration flags determine which formats will be supported. See the Supported formats page for more details of the available flags.

For example, to fetch and build FFmpeg release 4.0 for armeabi-v7a, arm64-v8a and x86 on Linux x86_64:

COMMON_OPTIONS="\
    --target-os=android \
    --disable-static \
    --enable-shared \
    --disable-doc \
    --disable-programs \
    --disable-everything \
    --disable-avdevice \
    --disable-avformat \
    --disable-swscale \
    --disable-postproc \
    --disable-avfilter \
    --disable-symver \
    --disable-swresample \
    --enable-avresample \
    --enable-decoder=vorbis \
    --enable-decoder=opus \
    --enable-decoder=flac \
    " && \
cd "${FFMPEG_EXT_PATH}" && \
(git -C ffmpeg pull || git clone git://source.ffmpeg.org/ffmpeg ffmpeg) && \
cd ffmpeg && git checkout release/4.0 && \
./configure \
    --libdir=android-libs/armeabi-v7a \
    --arch=arm \
    --cpu=armv7-a \
    --cross-prefix="${NDK_PATH}/toolchains/arm-linux-androideabi-4.9/prebuilt/${HOST_PLATFORM}/bin/arm-linux-androideabi-" \
    --sysroot="${NDK_PATH}/platforms/android-9/arch-arm/" \
    --extra-cflags="-march=armv7-a -mfloat-abi=softfp" \
    --extra-ldflags="-Wl,--fix-cortex-a8" \
    --extra-ldexeflags=-pie \
    ${COMMON_OPTIONS} \
    && \
make -j4 && make install-libs && \
make clean && ./configure \
    --libdir=android-libs/arm64-v8a \
    --arch=aarch64 \
    --cpu=armv8-a \
    --cross-prefix="${NDK_PATH}/toolchains/aarch64-linux-android-4.9/prebuilt/${HOST_PLATFORM}/bin/aarch64-linux-android-" \
    --sysroot="${NDK_PATH}/platforms/android-21/arch-arm64/" \
    --extra-ldexeflags=-pie \
    ${COMMON_OPTIONS} \
    && \
make -j4 && make install-libs && \
make clean && ./configure \
    --libdir=android-libs/x86 \
    --arch=x86 \
    --cpu=i686 \
    --cross-prefix="${NDK_PATH}/toolchains/x86-4.9/prebuilt/${HOST_PLATFORM}/bin/i686-linux-android-" \
    --sysroot="${NDK_PATH}/platforms/android-9/arch-x86/" \
    --extra-ldexeflags=-pie \
    --disable-asm \
    ${COMMON_OPTIONS} \
    && \
make -j4 && make install-libs && \
make clean

• Build the JNI native libraries, setting APP_ABI to include the architectures built in the previous step. For example:

cd "${FFMPEG_EXT_PATH}" && \
${NDK_PATH}/ndk-build APP_ABI="armeabi-v7a arm64-v8a x86" -j4

Using the extension

Once you've followed the instructions above to check out, build and depend on the extension, the next step is to tell ExoPlayer to use FfmpegAudioRenderer. How you do this depends on which player API you're using:

• If you're passing a DefaultRenderersFactory to ExoPlayerFactory.newSimpleInstance, you can enable using the extension by setting the extensionRendererMode parameter of the DefaultRenderersFactory constructor to EXTENSION_RENDERER_MODE_ON. This will use FfmpegAudioRenderer for playback if MediaCodecAudioRenderer doesn't support the input format. Pass EXTENSION_RENDERER_MODE_PREFER to give FfmpegAudioRenderer priority over MediaCodecAudioRenderer.
• If you've subclassed DefaultRenderersFactory, add an FfmpegAudioRenderer to the output list in buildAudioRenderers. ExoPlayer will use the first Renderer in the list that supports the input media format.
• If you've implemented your own RenderersFactory, return an FfmpegAudioRenderer instance from createRenderers. ExoPlayer will use the first Renderer in the returned array that supports the input media format.
• If you're using ExoPlayerFactory.newInstance, pass an FfmpegAudioRenderer in the array of Renderers. ExoPlayer will use the first Renderer in the list that supports the input media format.

Note: These instructions assume you're using DefaultTrackSelector. If you have a custom track selector the choice of Renderer is up to your implementation, so you need to make sure you are passing an FfmpegAudioRenderer to the player, then implement your own logic to use the renderer for a given track.

Links

• Javadoc: Classes matching com.google.android.exoplayer2.ext.ffmpeg.* belong to this module.