Android使用AudioRecord、MediaRecorder录制音频

package com.azhon.audio; import android.media.MediaCodec; import android.media.MediaCodecInfo; import android.media.MediaFormat; import java.io.IOException; import java.nio.ByteBuffer; /** * 项目名: JTTProtocol * 包名 com.azhon.jtt808.audio * 文件名: PCMEncoderAAC * 创建时间: 2020/2/29 on 16:17 * 描述: TODO 将pcm音频编码成AAC * * @author 阿钟 */ public class PCMEncoderAAC { //比特率 private final static int KEY_BIT_RATE = 96000; //读取数据的最大字节数 private final static int KEY_MAX_INPUT_SIZE = 1024 * 1024; //声道数 private final static int CHANNEL_COUNT = 2; private MediaCodec mediaCodec; private ByteBuffer[] encodeInputBuffers; private ByteBuffer[] encodeOutputBuffers; private MediaCodec.BufferInfo encodeBufferInfo; private EncoderListener encoderListener; public PCMEncoderAAC(int sampleRate, EncoderListener encoderListener) { this.encoderListener = encoderListener; init(sampleRate); } /** * 初始化AAC编码器 */ private void init(int sampleRate) { try { //参数对应-> mime type、采样率、声道数 MediaFormat encodeFormat = MediaFormat.createAudioFormat(MediaFormat.MIMETYPE_AUDIO_AAC, sampleRate, CHANNEL_COUNT); //比特率 encodeFormat.setInteger(MediaFormat.KEY_BIT_RATE, KEY_BIT_RATE); encodeFormat.setInteger(MediaFormat.KEY_AAC_PROFILE, MediaCodecInfo.CodecProfileLevel.AACObjectLC); encodeFormat.setInteger(MediaFormat.KEY_MAX_INPUT_SIZE, KEY_MAX_INPUT_SIZE); mediaCodec = MediaCodec.createEncoderByType(MediaFormat.MIMETYPE_AUDIO_AAC); mediaCodec.configure(encodeFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE); } catch (IOException e) { e.printStackTrace(); } mediaCodec.start(); encodeInputBuffers = mediaCodec.getInputBuffers(); encodeOutputBuffers = mediaCodec.getOutputBuffers(); encodeBufferInfo = new MediaCodec.BufferInfo(); } /** * @param data */ public void encodeData(byte[] data) { //dequeueInputBuffer（time）需要传入一个时间值，-1表示一直等待，0表示不等待有可能会丢帧，其他表示等待多少毫秒 //获取输入缓存的index int inputIndex = mediaCodec.dequeueInputBuffer(-1); if (inputIndex >= 0) { ByteBuffer inputByteBuf = encodeInputBuffers[inputIndex]; inputByteBuf.clear(); //添加数据 inputByteBuf.put(data); //限制ByteBuffer的访问长度 inputByteBuf.limit(data.length); //把输入缓存塞回去给MediaCodec mediaCodec.queueInputBuffer(inputIndex, 0, data.length, 0, 0); } //获取输出缓存的index int outputIndex = mediaCodec.dequeueOutputBuffer(encodeBufferInfo, 0); while (outputIndex >= 0) { //获取缓存信息的长度 int byteBufSize = encodeBufferInfo.size; //添加ADTS头部后的长度 int bytePacketSize = byteBufSize + 7; //拿到输出Buffer ByteBuffer outPutBuf = encodeOutputBuffers[outputIndex]; outPutBuf.position(encodeBufferInfo.offset); outPutBuf.limit(encodeBufferInfo.offset + encodeBufferInfo.size); byte[] aacData = new byte[bytePacketSize]; //添加ADTS头部 addADTStoPacket(aacData, bytePacketSize); /* get（byte[] dst,int offset,int length）:ByteBuffer从position位置开始读，读取length个byte，并写入dst下 标从offset到offset + length的区域 */ outPutBuf.get(aacData, 7, byteBufSize); outPutBuf.position(encodeBufferInfo.offset); //编码成功 if (encoderListener != null) { encoderListener.encodeAAC(aacData); } //释放 mediaCodec.releaseOutputBuffer(outputIndex, false); outputIndex = mediaCodec.dequeueOutputBuffer(encodeBufferInfo, 0); } } /** * 添加ADTS头 */ private void addADTStoPacket(byte[] packet, int packetLen) { // AAC LC int profile = 2; // 44.1KHz int freqIdx = 4; // CPE int chanCfg = 2; // fill in ADTS data packet[0] = (byte) 0xFF; packet[1] = (byte) 0xF9; packet[2] = (byte) (((profile - 1) << 6) + (freqIdx << 2) + (chanCfg >> 2)); packet[3] = (byte) (((chanCfg & 3) << 6) + (packetLen >> 11)); packet[4] = (byte) ((packetLen & 0x7FF) >> 3); packet[5] = (byte) (((packetLen & 7) << 5) + 0x1F); packet[6] = (byte) 0xFC; } public interface EncoderListener { void encodeAAC(byte[] data); } }