android13/external/exoplayer/tree_8e57d3715f9092d5ec54ebe2e538f34bfcc34479/extensions/av1

ExoPlayer AV1 module

The AV1 module provides Libgav1VideoRenderer, which uses libgav1 native library to decode AV1 videos.

License note

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

Build instructions (Linux, macOS)

To use the module you need to clone this GitHub project and depend on its modules locally. Instructions for doing this can be found in the top level README.

In addition, it's necessary to fetch cpu_features library and libgav1 with its dependencies as follows:

• Set the following environment variables:

cd "<path to project checkout>"
AV1_MODULE_PATH="$(pwd)/extensions/av1/src/main"

• Fetch cpu_features library:

cd "${AV1_MODULE_PATH}/jni" && \
git clone https://github.com/google/cpu_features

• Fetch libgav1:

cd "${AV1_MODULE_PATH}/jni" && \
git clone https://chromium.googlesource.com/codecs/libgav1

• Fetch Abseil:

cd "${AV1_MODULE_PATH}/jni/libgav1" && \
git clone https://github.com/abseil/abseil-cpp.git third_party/abseil-cpp

• Install CMake.

Having followed these steps, gradle will build the module automatically when run on the command line or via Android Studio, using CMake and Ninja to configure and build libgav1 and the module's JNI wrapper library.

Build instructions (Windows)

We do not provide support for building this module on Windows, however it should be possible to follow the Linux instructions in Windows PowerShell.

Using the module

Once you've followed the instructions above to check out, build and depend on the module, the next step is to tell ExoPlayer to use Libgav1VideoRenderer. How you do this depends on which player API you're using:

• If you're passing a DefaultRenderersFactory to ExoPlayer.Builder, you can enable using the module by setting the extensionRendererMode parameter of the DefaultRenderersFactory constructor to EXTENSION_RENDERER_MODE_ON. This will use Libgav1VideoRenderer for playback if MediaCodecVideoRenderer doesn't support decoding the input AV1 stream. Pass EXTENSION_RENDERER_MODE_PREFER to give Libgav1VideoRenderer priority over MediaCodecVideoRenderer.
• If you've subclassed DefaultRenderersFactory, add a Libvgav1VideoRenderer to the output list in buildVideoRenderers. ExoPlayer will use the first Renderer in the list that supports the input media format.
• If you've implemented your own RenderersFactory, return a Libgav1VideoRenderer instance from createRenderers. ExoPlayer will use the first Renderer in the returned array that supports the input media format.
• If you're using ExoPlayer.Builder, pass a Libgav1VideoRenderer 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. You need to make sure you are passing a Libgav1VideoRenderer to the player and then you need to implement your own logic to use the renderer for a given track.

Using the module in the demo application

To try out playback using the module in the demo application, see enabling extension decoders.

Rendering options

There are two possibilities for rendering the output Libgav1VideoRenderer gets from the libgav1 decoder:

• GL rendering using GL shader for color space conversion

  • If you are using ExoPlayer with StyledPlayerView, enable this option by setting the surface_type of the view to be video_decoder_gl_surface_view.
  • Otherwise, enable this option by sending Libgav1VideoRenderer a message of type Renderer.MSG_SET_VIDEO_OUTPUT with an instance of VideoDecoderOutputBufferRenderer as its object. VideoDecoderGLSurfaceView is the concrete VideoDecoderOutputBufferRenderer implementation used by StyledPlayerView.

• Native rendering using ANativeWindow

  • If you are using ExoPlayer with StyledPlayerView, this option is enabled by default.
  • Otherwise, enable this option by sending Libgav1VideoRenderer a message of type Renderer.MSG_SET_VIDEO_OUTPUT with an instance of SurfaceView as its object.

Note: Although the default option uses ANativeWindow, based on our testing the GL rendering mode has better performance, so should be preferred

Links

• Javadoc