Android 音频开发 目录
- Android音频开发（1）：音频相关知识
- Android音频开发（2）：使用AudioRecord录制pcm格式音频
- Android音频开发（3）：使用AudioRecord实现录音的暂停和恢复
- Android音频开发（4）：PCM转WAV格式音频
- Android音频开发（5）：Mp3的录制 - 编译Lame源码
- Android音频开发（6）：Mp3的录制 - 使用Lame实时录制MP3格式音频
- Android音频开发（7）：音乐可视化-FFT频谱图
项目地址
https://github.com/zhaolewei/ZlwAudioRecorder
上一篇主要写了AudioRecord实现音频录制的开始和停止，AudioRecord并没有暂停和恢复播放功能的API,所以需要手动实现
一、解决办法
思路很简单，现在可以实现音频的文件录制和停止，并生成pcm文件，那么暂停时将这次文件先保存下来，恢复播放后开始新一轮的录制，那么最后会生成多个pcm音频，再将这些pcm文件进行合并，这样就实现了暂停/恢复的功能了。
二、实现
- 实现的重点在于如何控制录音的状态
/**
* @author zhaolewei on 2018/7/10.
*/
public class RecordHelper {
private volatile RecordState state = RecordState.IDLE;
private AudioRecordThread audioRecordThread;
private File recordFile = null;
private File tmpFile = null;
private List files = new ArrayList<>();
public void start(String filePath, RecordConfig config) {
this.currentConfig = config;
if (state != RecordState.IDLE) {
Logger.e(TAG, "状态异常当前状态： %s", state.name());
return;
}
recordFile = new File(filePath);
String tempFilePath = getTempFilePath();
Logger.i(TAG, "tmpPCM File: %s", tempFilePath);
tmpFile = new File(tempFilePath);
audioRecordThread = new AudioRecordThread();
audioRecordThread.start();
}
public void stop() {
if (state == RecordState.IDLE) {
Logger.e(TAG, "状态异常当前状态： %s", state.name());
return;
}
//若在暂停中直接停止，则直接合并文件即可
if (state == RecordState.PAUSE) {
makeFile();
state = RecordState.IDLE;
} else {
state = RecordState.STOP;
}
}
public void pause() {
if (state != RecordState.RECORDING) {
Logger.e(TAG, "状态异常当前状态： %s", state.name());
return;
}
state = RecordState.PAUSE;
}
public void resume() {
if (state != RecordState.PAUSE) {
Logger.e(TAG, "状态异常当前状态： %s", state.name());
return;
}
String tempFilePath = getTempFilePath();
Logger.i(TAG, "tmpPCM File: %s", tempFilePath);
tmpFile = new File(tempFilePath);
audioRecordThread = new AudioRecordThread();
audioRecordThread.start();
}
private class AudioRecordThread extends Thread {
private AudioRecord audioRecord;
private int bufferSize;
AudioRecordThread() {
bufferSize = AudioRecord.getMinBufferSize(currentConfig.getFrequency(),
currentConfig.getChannel(), currentConfig.getEncoding()) * RECORD_AUDIO_BUFFER_TIMES;
audioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC, currentConfig.getFrequency(),
currentConfig.getChannel(), currentConfig.getEncoding(), bufferSize);
}
@Override
public void run() {
super.run();
state = RecordState.RECORDING;
notifyState();
Logger.d(TAG, "开始录制");
FileOutputStream fos = null;
try {
fos = new FileOutputStream(tmpFile);
audioRecord.startRecording();
byte[] byteBuffer = new byte[bufferSize];
while (state == RecordState.RECORDING) {
int end = audioRecord.read(byteBuffer, 0, byteBuffer.length);
fos.write(byteBuffer, 0, end);
fos.flush();
}
audioRecord.stop();
//1. 将本次录音的文件暂存下来，用于合并
files.add(tmpFile);
//2. 再此判断终止循环的状态是暂停还是停止，并做相应处理
if (state == RecordState.STOP) {
makeFile();
} else {
Logger.i(TAG, "暂停！");
}
} catch (Exception e) {
Logger.e(e, TAG, e.getMessage());
} finally {
try {
if (fos != null) {
fos.close();
}
} catch (IOException e) {
Logger.e(e, TAG, e.getMessage());
}
}
if (state != RecordState.PAUSE) {
state = RecordState.IDLE;
notifyState();
Logger.d(TAG, "录音结束");
}
}
}
private void makeFile() {
//合并文件
boolean mergeSuccess = mergePcmFiles(recordFile, files);
//TODO:转换wav
Logger.i(TAG, "录音完成！ path: %s ； 大小：%s", recordFile.getAbsoluteFile(), recordFile.length());
}
/**
* 合并Pcm文件
*
* @param recordFile 输出文件
* @param files 多个文件源
* @return 是否成功
*/
private boolean mergePcmFiles(File recordFile, List files) {
if (recordFile == null || files == null || files.size() <= 0) {
return false;
}
FileOutputStream fos = null;
BufferedOutputStream outputStream = null;
byte[] buffer = new byte[1024];
try {
fos = new FileOutputStream(recordFile);
outputStream = new BufferedOutputStream(fos);
for (int i = 0; i < files.size(); i++) {
BufferedInputStream inputStream = new BufferedInputStream(new FileInputStream(files.get(i)));
int readCount;
while ((readCount = inputStream.read(buffer)) > 0) {
outputStream.write(buffer, 0, readCount);
}
inputStream.close();
}
} catch (Exception e) {
Logger.e(e, TAG, e.getMessage());
return false;
} finally {
try {
if (fos != null) {
fos.close();
}
if (outputStream != null) {
outputStream.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
//3. 合并后记得删除缓存文件并清除list
for (int i = 0; i < files.size(); i++) {
files.get(i).delete();
}
files.clear();
return true;
}
}
其他
- 在此后如若需要添加录音状态回调，记得使用Handler做好线程切换。