Based on Sonic (speed , pitch and rate) , the demo for Android

Introduction

一个基于 Sonic(声音处理算法)的,音频 Speed,Pitch,Rate 调节 Demo
该 Demo 支持音频打开方式后直接可进行相关音频参数的调节,
或者手动选择本地音频,或者直接播放本 Demo 内置音频,
要播放在线音频可手动修改源码音频 Uri

Features

该 Demo 支持两种媒体引擎,都支持音频的变速功能.
一个是,基于 Exo 和 Sonic Java 算法
另一个是,基于 Presto 和 Sonic C 算法
-----------
另外界面部分中
含有一个 PlusMinusNum 自定义控件
支持数字的累加/递减(float/int:需要自己再修改)
支持长按连续累加/递减.....

CoreCode

protected boolean processOutputBuffer(long positionUs, long elapsedRealtimeUs, MediaCodec codec, ByteBuffer buffer, int bufferIndex, int bufferFlags, long bufferPresentationTimeUs, boolean shouldSkip) throws ExoPlaybackException {
    if (bufferIndex != this.bufferIndex) {
      this.bufferIndex = bufferIndex;
      if ((speed != 1.0f || pitch != 1.0f || rate != 1.0f) && initSonic(buffer.remaining())) {
        // =========@Sonic@=========
        int sonicProcessingSize;
        int position = buffer.position();

        // =========@Get the data and processing
        sonicProcessingSize = buffer.remaining();
        buffer.get(sonicBuffer, 0, sonicProcessingSize);
        sonic.writeBytesToStream(sonicBuffer, sonicProcessingSize);
        sonicProcessingSize = sonic.readBytesFromStream(sonicBuffer, sonicBuffer.length);

        // =========@Put the sonic processing data
        if (!buffer.isReadOnly()) {
          buffer.position(position);
          buffer.limit(position + sonicProcessingSize);
          buffer.put(sonicBuffer, 0, sonicProcessingSize);
          buffer.position(position);
        } else {//Use bufferSub replace buffer
          if (bufferSub == null || bufferSub.capacity() != sonicBuffer.length)
            bufferSub = ByteBuffer.wrap(sonicBuffer, 0, 0);
          bufferSub.position(0);
          bufferSub.limit(sonicProcessingSize);
        }
      } else if (bufferSub != null)
        bufferSub = null;
    }
    if (bufferSub != null && buffer.isReadOnly())
      buffer = bufferSub;

    return super.processOutputBuffer(positionUs, elapsedRealtimeUs, codec, buffer, bufferIndex, bufferFlags, bufferPresentationTimeUs, shouldSkip);
}

Usage

直接引用 K-Sonic 项目中的 library
library-exo: minSdkVer:JELLY_BEAN(16), SDK_INT<23 构建 SonicMediaCodecAudioRenderer 实现<23 兼容加速
library-presto: minSdkVer:GINGERBREAD(9), MediaExtractor MediaCodec Sonic 实现加速播放

License

MIT License

Copyright (c) 2017 K Sun <jcodeing@gmail.com>

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.