Android Low-Latency Audio Post-Processing with Superpowered - AudioPlayer Gist

AudioPlayer.java

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private class EffectAudioTrack extends AudioTrack {

        public EffectAudioTrack(int streamType, int sampleRateInHz, int channelConfig, int audioFormat, int bufferSizeInBytes, int mode) throws IllegalArgumentException {
            super(streamType, sampleRateInHz, channelConfig, audioFormat, bufferSizeInBytes, mode);
        }

        public EffectAudioTrack(int streamType, int sampleRateInHz, int channelConfig, int audioFormat, int bufferSizeInBytes, int mode, int sessionId) throws IllegalArgumentException {
            super(streamType, sampleRateInHz, channelConfig, audioFormat, bufferSizeInBytes, mode, sessionId);
        }

        public EffectAudioTrack(AudioAttributes attributes, AudioFormat format, int bufferSizeInBytes, int mode, int sessionId) throws IllegalArgumentException {
            super(attributes, format, bufferSizeInBytes, mode, sessionId);
        }

        @Override
        public int write(@NonNull ByteBuffer audioData, int sizeInBytes, int writeMode) {
            renderEffectNative(audioData, audioProps.getNrChannels());
            return super.write(audioData, sizeInBytes, writeMode);
        }
    }

    private native void renderEffectNative(ByteBuffer data, int channelCount);
}