content: /*
   * Copyright (C) 2016 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.google.android.exoplayer2.ext.opus;
  
  import android.os.Handler;
  import androidx.annotation.Nullable;
  import com.google.android.exoplayer2.C;
  import com.google.android.exoplayer2.Format;
  import com.google.android.exoplayer2.audio.AudioProcessor;
  import com.google.android.exoplayer2.audio.AudioRendererEventListener;
  import com.google.android.exoplayer2.audio.AudioSink;
  import com.google.android.exoplayer2.audio.AudioSink.SinkFormatSupport;
  import com.google.android.exoplayer2.audio.DecoderAudioRenderer;
  import com.google.android.exoplayer2.decoder.CryptoConfig;
  import com.google.android.exoplayer2.util.MimeTypes;
  import com.google.android.exoplayer2.util.TraceUtil;
  import com.google.android.exoplayer2.util.Util;
  
  /** Decodes and renders audio using the native Opus decoder. */
  public class LibopusAudioRenderer extends DecoderAudioRenderer<OpusDecoder> {
  
    private static final String TAG = "LibopusAudioRenderer";
    /** The number of input and output buffers. */
    private static final int NUM_BUFFERS = 16;
    /** The default input buffer size. */
    private static final int DEFAULT_INPUT_BUFFER_SIZE = 960 * 6;
  
    public LibopusAudioRenderer() {
      this(/* eventHandler= */ null, /* eventListener= */ null);
    }
  
    /**
     * Creates a new instance.
     *
     * @param eventHandler A handler to use when delivering events to {@code eventListener}. May be
     *     null if delivery of events is not required.
     * @param eventListener A listener of events. May be null if delivery of events is not required.
     * @param audioProcessors Optional {@link AudioProcessor}s that will process audio before output.
     */
    public LibopusAudioRenderer(
        @Nullable Handler eventHandler,
        @Nullable AudioRendererEventListener eventListener,
        AudioProcessor... audioProcessors) {
      super(eventHandler, eventListener, audioProcessors);
    }
  
    /**
     * Creates a new instance.
     *
     * @param eventHandler A handler to use when delivering events to {@code eventListener}. May be
     *     null if delivery of events is not required.
     * @param eventListener A listener of events. May be null if delivery of events is not required.
     * @param audioSink The sink to which audio will be output.
     */
    public LibopusAudioRenderer(
        @Nullable Handler eventHandler,
        @Nullable AudioRendererEventListener eventListener,
        AudioSink audioSink) {
      super(eventHandler, eventListener, audioSink);
    }
  
    @Override
    public String getName() {
      return TAG;
    }
  
    @Override
    protected @C.FormatSupport int supportsFormatInternal(Format format) {
      boolean drmIsSupported = OpusLibrary.supportsCryptoType(format.cryptoType);
      if (!OpusLibrary.isAvailable()
          || !MimeTypes.AUDIO_OPUS.equalsIgnoreCase(format.sampleMimeType)) {
        return C.FORMAT_UNSUPPORTED_TYPE;
      } else if (!sinkSupportsFormat(
          Util.getPcmFormat(C.ENCODING_PCM_16BIT, format.channelCount, format.sampleRate))) {
        return C.FORMAT_UNSUPPORTED_SUBTYPE;
      } else if (!drmIsSupported) {
        return C.FORMAT_UNSUPPORTED_DRM;
      } else {
        return C.FORMAT_HANDLED;
      }
    }
  
    /** {@inheritDoc} */
    @Override
    protected final OpusDecoder createDecoder(Format format, @Nullable CryptoConfig cryptoConfig)
        throws OpusDecoderException {
      TraceUtil.beginSection("createOpusDecoder");
      @SinkFormatSupport
      int formatSupport =
          getSinkFormatSupport(
              Util.getPcmFormat(C.ENCODING_PCM_FLOAT, format.channelCount, format.sampleRate));
      boolean outputFloat = formatSupport == AudioSink.SINK_FORMAT_SUPPORTED_DIRECTLY;
  
      int initialInputBufferSize =
          format.maxInputSize != Format.NO_VALUE ? format.maxInputSize : DEFAULT_INPUT_BUFFER_SIZE;
      OpusDecoder decoder =
          new OpusDecoder(
              NUM_BUFFERS,
              NUM_BUFFERS,
              initialInputBufferSize,
              format.initializationData,
              cryptoConfig,
              outputFloat);
      decoder.experimentalSetDiscardPaddingEnabled(experimentalGetDiscardPaddingEnabled());
  
      TraceUtil.endSection();
      return decoder;
    }
  
    /** {@inheritDoc} */
    @Override
    protected final Format getOutputFormat(OpusDecoder decoder) {
      @C.PcmEncoding
      int pcmEncoding = decoder.outputFloat ? C.ENCODING_PCM_FLOAT : C.ENCODING_PCM_16BIT;
      return Util.getPcmFormat(pcmEncoding, decoder.channelCount, OpusDecoder.SAMPLE_RATE);
    }
  
    /**
     * Returns true if support for padding removal from the end of decoder output buffer should be
     * enabled.
     *
     * <p>This method is experimental, and will be renamed or removed in a future release.
     */
    protected boolean experimentalGetDiscardPaddingEnabled() {
      return false;
    }
  }
  