ExoPlayer 重写 OpusReader 思路

2021 年 12 月 17 日
本文字数：1947 字
阅读完需：约 6 分钟

1.需求

使用 ExoPlayer 来播放远程的 TS 在线文件
由于特殊的原因导致，客户端的音频编码采用 opus，这也导致了流媒体服务存储的录音文件的音频编码也是 opus。我们测试过多种 PC 端播放器，PotPlayer 和 VLC、MediaPlayer，仅有 VLC 可以正常播放和解码，而 PotPlayer 只能渲染视频画面，无法播放声音。

2.分析

我们的思路是，在 ExoPlayer 的 TsExtractor 中加入 opus 解码的支持，重写一个 OpusReader 来实现对在线 TS 文件的音频解码。


PlayerActivity.onCreate->DemoUtil.getDataSourceFactory->DemoUtil.getHttpDataSourceFactory->CronetDataSource.Factory->CronetEngineWrapper->com.google.android.exoplayer2.upstream.DefaultDataSource#open->DefaultMediaSourceFactory
SimpleExoPlayer->MediaSourceFactory->DefaultMediaSourceFactory->CronetDataSource->->DefaultExtractorsFactory->FileTypes.TS->TsExtractor

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3.源码

DefaultTsPayloadReaderFactory.java


  @Override  @Nullable  public TsPayloadReader createPayloadReader(int streamType, EsInfo esInfo) {    Log.e("cclin", String.format("createPayloadReader: 0x%x-%s-%s", streamType, esInfo.streamType, esInfo.language));    switch (streamType) {      case TsExtractor.TS_STREAM_TYPE_MPA:      case TsExtractor.TS_STREAM_TYPE_MPA_LSF:        return new PesReader(new MpegAudioReader(esInfo.language));      case TsExtractor.TS_STREAM_TYPE_AAC_ADTS:        return isSet(FLAG_IGNORE_AAC_STREAM)            ? null : new PesReader(new AdtsReader(false, esInfo.language));      case TsExtractor.TS_STREAM_TYPE_AAC_LATM:        return isSet(FLAG_IGNORE_AAC_STREAM)            ? null : new PesReader(new LatmReader(esInfo.language));      case TsExtractor.TS_STREAM_TYPE_AC3:      case TsExtractor.TS_STREAM_TYPE_E_AC3:        return new PesReader(new Ac3Reader(esInfo.language));      case TsExtractor.TS_STREAM_TYPE_AC4:        return new PesReader(new Ac4Reader(esInfo.language));      case TsExtractor.TS_STREAM_TYPE_HDMV_DTS:        if (!isSet(FLAG_ENABLE_HDMV_DTS_AUDIO_STREAMS)) {          return null;        }        // Fall through.      case TsExtractor.TS_STREAM_TYPE_DTS:        return new PesReader(new DtsReader(esInfo.language));      case TsExtractor.TS_STREAM_TYPE_H262:        return new PesReader(new H262Reader(buildUserDataReader(esInfo)));      case TsExtractor.TS_STREAM_TYPE_H263:        return new PesReader(new H263Reader(buildUserDataReader(esInfo)));      case TsExtractor.TS_STREAM_TYPE_H264:        return isSet(FLAG_IGNORE_H264_STREAM) ? null            : new PesReader(new H264Reader(buildSeiReader(esInfo),                isSet(FLAG_ALLOW_NON_IDR_KEYFRAMES), isSet(FLAG_DETECT_ACCESS_UNITS)));      case TsExtractor.TS_STREAM_TYPE_H265:        return new PesReader(new H265Reader(buildSeiReader(esInfo)));      case TsExtractor.TS_STREAM_TYPE_SPLICE_INFO:        return isSet(FLAG_IGNORE_SPLICE_INFO_STREAM)            ? null            : new SectionReader(new PassthroughSectionPayloadReader(MimeTypes.APPLICATION_SCTE35));      case TsExtractor.TS_STREAM_TYPE_ID3:        return new PesReader(new Id3Reader());      case TsExtractor.TS_STREAM_TYPE_DVBSUBS:        return new PesReader(            new DvbSubtitleReader(esInfo.dvbSubtitleInfos));      case TsExtractor.TS_STREAM_TYPE_AIT:        return new SectionReader(new PassthroughSectionPayloadReader(MimeTypes.APPLICATION_AIT));      case 6:        return new PesReader(new OpusReader());      default:        return null;    }  }

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OpusReader.java


public class OpusReader implements ElementaryStreamReader {
  private static final String TAG = "OpusReader";
  @Override  public void seek() {
  }
  @Override  public void createTracks(ExtractorOutput extractorOutput,      PesReader.TrackIdGenerator idGenerator) {
  }
  @Override  public void packetStarted(long pesTimeUs, int flags) {
  }
  @Override  public void consume(ParsableByteArray data) throws ParserException {
  }
  @Override  public void packetFinished() {
  }}