Changing playback speed in Exoplayer

问题

I'm looking to implement an audio player with variable speed playback (1.0x, 1.25x, 1.5x) like typical audiobook players currently on the market do. I would like to use Google's Exoplayer library as my audioplayer library however they don't appear to support variable speed playback. Any ideas on how to implement this, or any extensions that do support this?

回答1:

The function setPlaybackSpeed() was removed and now you set the playback speed via:

    PlaybackParameters param = new PlaybackParameters(speed);
    mExoPlayer.setPlaybackParameters(param);

speed is a float number. Normal speed is 1f and double the speed would be 2f.

回答2:

All you need is https://github.com/waywardgeek/sonic/blob/master/Sonic.java

If you look at MediaCodecAudioTrackRenderer.java, you can get the output buffer (decoded by MediaCodec) from ExoPlayer in method processOutputBuffer and process it through Sonic.java accordingly before sending it to AudioTrack.

Following document explains how to use libsonic https://github.com/waywardgeek/sonic/blob/master/doc/index.md

回答3:

Try This

I have followed all the answer nothing worked, so i have tried the below solution, it works for me

PlaybackParams param = new PlaybackParams();
param.setSpeed(1f);// 1f is 1x, 2f is 2x 
exoPlayer.setPlaybackParams(param);

回答4:

You should take a look this project, which was very useful for me: https://github.com/AmrMohammed89/exoplayer2.4.0_speedup

Inside SimpleExoPlayer, I implemented the next methods:

 private final ExoPlayer player;
private float playbackSpeed;

float SPEED_NORMAL = 1f;
float SPEED_MEDIUM = 1.5f;
float SPEED_HIGH = 2f;


 @Override
public float getPlaybackSpeed() {
    return playbackSpeed;
}

@Override
public void setPlaybackSpeed(float speed) {
    playbackSpeed = speed;
    player.setPlaybackSpeed(speed);
}

@Override
public void changePlaybackSpeed() {
    if (playbackSpeed == SPEED_MEDIUM) {
        player.setPlaybackSpeed(SPEED_HIGH);
        playbackSpeed = SPEED_HIGH;
    } else if (playbackSpeed == SPEED_HIGH) {
        player.setPlaybackSpeed(SPEED_NORMAL);
        playbackSpeed = SPEED_NORMAL;
    } else {
        player.setPlaybackSpeed(SPEED_MEDIUM);
        playbackSpeed = SPEED_MEDIUM;
    }
}

I set and saved the speed that way due to there was a bug when I tried to get the last saved speed. So follow that mechanism and it will work perfectly.

Cheers

来源：https://stackoverflow.com/questions/31947460/changing-playback-speed-in-exoplayer