我正在尝试录制一个wav文件并在android中读取和保存wav文件的数据。除了我在Matlab中读取的值与我在android中保存的数据中的值的差异之外，工作正常 这是我的代码
private static final int RECORDER_BPP = 16;
private static final String AUDIO_RECORDER_FILE_EXT_WAV = ".wav";
private static final String AUDIO_RECORDER_FOLDER = "AudioRecorder";
private static final String AUDIO_RECORDER_TEMP_FILE = "record_temp.raw";
private static final int RECORDER_SAMPLERATE = 44100;
private static final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;
private static final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;
private AudioRecord recorder = null;
private int bufferSize = 0;
private Thread recordingThread = null;
private boolean isRecording = false;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
setButtonHandlers();
enableButtons(false);
bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE, RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING);
}
private void setButtonHandlers() {
((Button) findViewById(R.id.btnStart)).setOnClickListener(btnClick);
((Button) findViewById(R.id.btnStop)).setOnClickListener(btnClick);
}
private void enableButton(int id, boolean isEnable) {
((Button) findViewById(id)).setEnabled(isEnable);
}
private void enableButtons(boolean isRecording) {
enableButton(R.id.btnStart, !isRecording);
enableButton(R.id.btnStop, isRecording);
}
private String getFilename() {
String filepath = Environment.getExternalStorageDirectory().getPath();
File file = new File(filepath, AUDIO_RECORDER_FOLDER);
if ( !file.exists()) {
file.mkdirs();
}
return (file.getAbsolutePath() + "/" + 11 + AUDIO_RECORDER_FILE_EXT_WAV);
}
private String getTempFilename() {
String filepath = Environment.getExternalStorageDirectory().getPath();
File file = new File(filepath, AUDIO_RECORDER_FOLDER);
if ( !file.exists()) {
file.mkdirs();
}
File tempFile = new File(filepath, AUDIO_RECORDER_TEMP_FILE);
if (tempFile.exists())
tempFile.delete();
return (file.getAbsolutePath() + "/" + AUDIO_RECORDER_TEMP_FILE);
}
private String getfftFilename() {
String filepath = Environment.getExternalStorageDirectory().getPath();
File file = new File(filepath, AUDIO_RECORDER_FOLDER);
if ( !file.exists()) {
file.mkdirs();
}
return (file.getAbsolutePath() + "/" + "fft" + ".txt");
}
private void startRecording() {
recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
RECORDER_SAMPLERATE, RECORDER_CHANNELS, RECORDER_AUDIO_ENCODING, bufferSize);
recorder.startRecording();
isRecording = true;
recordingThread = new Thread(new Runnable() {
@Override
public void run() {
writeAudioDataToFile();
}
}, "AudioRecorder Thread");
recordingThread.start();
}
private void writeAudioDataToFile() {
byte data[] = new byte[bufferSize];
String filename = getTempFilename();
FileOutputStream os = null;
try {
os = new FileOutputStream(filename);
}
catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
int read = 0;
if (null != os) {
while (isRecording) {
read = recorder.read(data, 0, bufferSize);
if (AudioRecord.ERROR_INVALID_OPERATION != read) {
try {
os.write(data);
}
catch (IOException e) {
e.printStackTrace();
}
}
}
}
try {
os.close();
}
catch (IOException e) {
e.printStackTrace();
}
}
private void stopRecording() {
if (null != recorder) {
isRecording = false;
recorder.stop();
recorder.release();
recorder = null;
recordingThread = null;
}
copyWaveFile(getTempFilename(), getFilename());
////coding(getTempFilename(), getrainroom(), getstegan());
////decoding(getstegan(), getdecodeFilename(), getrainroom());
fftbegir(getTempFilename(), getfftFilename());
deleteTempFile();
}
private void deleteTempFile() {
File file = new File(getTempFilename());
file.delete();
}
private void copyWaveFile(String inFilename, String outFilename) {
FileInputStream in = null;
FileOutputStream out = null;
long totalAudioLen = 0;
long totalDataLen = totalAudioLen + 36;
long longSampleRate = RECORDER_SAMPLERATE;
int channels = 1;
long byteRate = RECORDER_BPP * RECORDER_SAMPLERATE * channels / 8;
byte[] data = new byte[bufferSize];
try {
in = new FileInputStream(inFilename);
out = new FileOutputStream(outFilename);
totalAudioLen = in.getChannel().size();
totalDataLen = totalAudioLen + 36;
AppLog.logString("File size: " + totalDataLen);
WriteWaveFileHeader(out, totalAudioLen, totalDataLen,
longSampleRate, channels, byteRate);
while (in.read(data) != -1) {
out.write(data);
}
in.close();
out.close();
}
catch (FileNotFoundException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
}
private void fftbegir(String input, String output) {
FileInputStream in5 = null;
FileOutputStream out5 = null;
FileOutputStream stream = null;
byte[] data7 = new byte[10000];
double[] data8;
long totalAudioLen = 0;
long totalDataLen = totalAudioLen + 36;
long longSampleRate = RECORDER_SAMPLERATE;
int channels = 1;
int i = 0;
int r, k, l;
double b;
int m = 2;
long byteRate = RECORDER_BPP * RECORDER_SAMPLERATE * channels / 8;
String filepath = Environment.getExternalStorageDirectory().getPath();
File tempFile = new File(filepath, AUDIO_RECORDER_TEMP_FILE);
try {
in5 = new FileInputStream(input);
out5 = new FileOutputStream(output);
String strI = "nxkxaprojext;)";
out5.write(strI.getBytes());
AppLog.logString("File size: " + totalDataLen);
totalAudioLen = in5.getChannel().size();
strI = Long.toString(totalAudioLen);
out5.write(strI.getBytes());
out5.write(" ".getBytes());
data8 = SoundDataUtils.load16BitPCMRawDataFileAsDoubleArray();
l = data8.length;
strI = Integer.toString(l);
out5.write(strI.getBytes());
out5.write(" ".getBytes());
while (l > m) {
m = m * 2;
}
strI = Integer.toString(m);
out5.write(strI.getBytes());
out5.write(" ".getBytes());
strI = Double.toString(data8[50]);
out5.write(strI.getBytes());
Complex[] x = new Complex[m];
while (i < l) {
strI = Double.toString(data8[i]);
out5.write(strI.getBytes());
out5.write(" ".getBytes());
//x[i] = new Complex(data8[i], 0);
i++;
}
in5.close();
///i--;
///for (i = l; i < m; i++) {
/// x[i] = new Complex(0, 0);
/// }
/// FFT f = new FFT();
//// Complex[] y = f.fft(x);
/*try {
for (i = 0; i < m; i++) {
b = y[i].re();
strI = Double.toString(b);
out5.write(strI.getBytes());
out5.write(" ".getBytes());
b = y[i].im();
strI = Double.toString(b);
out5.write(strI.getBytes());
out5.write("j".getBytes());
out5.write(" ".getBytes());
}
}*/// finally {
/// out5.close();
////}
}
catch (FileNotFoundException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
}
private void WriteWaveFileHeader(
FileOutputStream out, long totalAudioLen,
long totalDataLen, long longSampleRate, int channels,
long byteRate) throws IOException {
byte[] header = new byte[44];
header[0] = 'R'; // RIFF/WAVE header
header[1] = 'I';
header[2] = 'F';
header[3] = 'F';
header[4] = (byte) (totalDataLen & 0xff);
header[5] = (byte) ((totalDataLen >> 8) & 0xff);
header[6] = (byte) ((totalDataLen >> 16) & 0xff);
header[7] = (byte) ((totalDataLen >> 24) & 0xff);
header[8] = 'W';
header[9] = 'A';
header[10] = 'V';
header[11] = 'E';
header[12] = 'f'; // 'fmt ' chunk
header[13] = 'm';
header[14] = 't';
header[15] = ' ';
header[16] = 16; // 4 bytes: size of 'fmt ' chunk
header[17] = 0;
header[18] = 0;
header[19] = 0;
header[20] = 1; // format = 1
header[21] = 0;
header[22] = (byte) channels;
header[23] = 0;
header[24] = (byte) (longSampleRate & 0xff);
header[25] = (byte) ((longSampleRate >> 8) & 0xff);
header[26] = (byte) ((longSampleRate >> 16) & 0xff);
header[27] = (byte) ((longSampleRate >> 24) & 0xff);
header[28] = (byte) (byteRate & 0xff);
header[29] = (byte) ((byteRate >> 8) & 0xff);
header[30] = (byte) ((byteRate >> 16) & 0xff);
header[31] = (byte) ((byteRate >> 24) & 0xff);
header[32] = (byte) (1 * 16 / 8); // block align
header[33] = 0;
header[34] = RECORDER_BPP; // bits per sample
header[35] = 0;
header[36] = 'd';
header[37] = 'a';
header[38] = 't';
header[39] = 'a';
header[40] = (byte) (totalAudioLen & 0xff);
header[41] = (byte) ((totalAudioLen >> 8) & 0xff);
header[42] = (byte) ((totalAudioLen >> 16) & 0xff);
header[43] = (byte) ((totalAudioLen >> 24) & 0xff);
out.write(header, 0, 44);
}
private View.OnClickListener btnClick = new View.OnClickListener() {
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btnStart: {
AppLog.logString("Start Recording");
enableButtons(true);
startRecording();
break;
}
case R.id.btnStop: {
AppLog.logString("Start Recording");
enableButtons(false);
stopRecording();
break;
}
}
}
};
和SoundDataUtils类代码是（在这个类中我尝试将16位转换为双倍）
public static double[] load16BitPCMRawDataFileAsDoubleArray() throws IOException {
String filepath = Environment.getExternalStorageDirectory().getPath();
File file = new File(filepath, "AudioRecorder");
if ( !file.exists()) {
file.mkdirs();
}
File tempFile = new File(filepath + "/AudioRecorder", "record_temp.raw");
InputStream in = null;
long size = tempFile.length();
try {
in = new FileInputStream(tempFile);
return readStreamAsDoubleArray(in, size);
}
catch (Exception e) {}
return null;
}
public static double[] readStreamAsDoubleArray(InputStream in, long size)
throws IOException {
int bufferSize = (int) (size / 2);
double[] result = new double[bufferSize];
DataInputStream is = new DataInputStream(in);
for (int i = 0; i < bufferSize; i++) {
result[i] = is.readShort() / 32768.0;
}
return result;
}
android中的前20个值： 0.8359375 0.2265625 0.1171875 0.8359375 -1.0 -0.8359375 0.9375 0.71875 -0.5078125 -0.34375 -0.8359375 -0.71875 -0.8828125 0.4453125 -0.218780517578125 0.960906982421875 -0.710968017578125 -0.156280517578125 -0.7890625 0.7734375 matlab中的前20个值：0.00326538085937500 0.000885009765625000 0.000457763671875000 0.00326538085937500 0.00390625000000000 0.00454711914062500 0.00366210937500000 0.00280761718750000 0.00582885742187500 0.00646972656250000 0.00454711914062500 0.00500488281250000 0.00436401367187500 0.00173950195312500 -0.000885009765625000 -0.00408935546875000 -0.00280761718750000 -0.000640869140625000 0.00473022460937500 0.00302124023437500
我花了很多时间来发现问题。 有人能帮我吗？谢谢！