我经历了堆栈溢出问题应用增益变化与我想知道的相同但是找不到答案我尝试了他们在上面问题链接中提到的答案没有适当或准确的解决方案我仍然得到声音（如 Walkie-对讲机）。任何一个做得正确的人。
public class Mediarec extends Activity {
public static final int SAMPLE_RATE = 16000;
private AudioRecord mRecorder;
private File mRecording;
private short[] mBuffer;
private final String startRecordingLabel = "Start recording";
private final String stopRecordingLabel = "Stop recording";
private boolean mIsRecording = false;
private ProgressBar mProgressBar;
short iGain= (short)1.0f;
CheckBox gain;
@Override
public void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_mediarec);
initRecorder();
gain = (CheckBox) findViewById(R.id.checkBox1);
mProgressBar = (ProgressBar) findViewById(R.id.progressBar);
final Button button = (Button) findViewById(R.id.start);
button.setText(startRecordingLabel);
gain.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {
if(gain.isChecked())
{
iGain = (short) Math.pow(10, 9.0 / 20.0 ) ;
// iGain = (short)2.0f;
}
else
{
iGain = (short) Math.pow(10, 3 / 20.0 ) ;
}
}
});
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(final View v) {
if (!mIsRecording) {
button.setText(stopRecordingLabel);
mIsRecording = true;
mRecorder.startRecording();
mRecording = getFile("raw");
startBufferedWrite(mRecording);
}
else {
button.setText(startRecordingLabel);
mIsRecording = false;
mRecorder.stop();
File waveFile = getFile("wav");
try {
rawToWave(mRecording, waveFile);
} catch (IOException e) {
Toast.makeText(Mediarec.this, e.getMessage(), Toast.LENGTH_SHORT).show();
}
Toast.makeText(Mediarec.this, "Recorded to " + waveFile.getName(),
Toast.LENGTH_SHORT).show();
}
}
});
}
@Override
public void onDestroy() {
mRecorder.release();
super.onDestroy();
}
private void initRecorder() {
int bufferSize = AudioRecord.getMinBufferSize(SAMPLE_RATE, AudioFormat.CHANNEL_IN_MONO,
AudioFormat.ENCODING_PCM_16BIT);
mBuffer = new short[bufferSize];
mRecorder = new AudioRecord(MediaRecorder.AudioSource.MIC, SAMPLE_RATE, AudioFormat.CHANNEL_IN_MONO,
AudioFormat.ENCODING_PCM_16BIT, bufferSize);
}
private void startBufferedWrite(final File file) {
new Thread(new Runnable() {
@Override
public void run() {
DataOutputStream output = null;
try {
output = new DataOutputStream(new BufferedOutputStream(new FileOutputStream(file)));
while (mIsRecording) {
double sum = 0;
int readSize = mRecorder.read(mBuffer, 0, mBuffer.length);
for (int i = 0; i < readSize; i++) {
output.writeShort(mBuffer[i]);
sum += mBuffer[i] * mBuffer[i];
}
if (readSize > 0) {
final double amplitude = sum / readSize;
mProgressBar.setProgress((int) Math.sqrt(amplitude));
}
}
} catch (IOException e) {
Toast.makeText(Mediarec.this, e.getMessage(), Toast.LENGTH_SHORT).show();
} finally {
mProgressBar.setProgress(0);
if (output != null) {
try {
output.flush();
} catch (IOException e) {
Toast.makeText(Mediarec.this, e.getMessage(), Toast.LENGTH_SHORT)
.show();
} finally {
try {
output.close();
} catch (IOException e) {
Toast.makeText(Mediarec.this, e.getMessage(), Toast.LENGTH_SHORT)
.show();
}
}
}
}
}
}).start();
}
private void rawToWave(final File rawFile, final File waveFile) throws IOException {
byte[] rawData = new byte[(int) rawFile.length()];
DataInputStream input = null;
try {
input = new DataInputStream(new FileInputStream(rawFile));
input.read(rawData);
} finally {
if (input != null) {
input.close();
}
}
DataOutputStream output = null;
try {
output = new DataOutputStream(new FileOutputStream(waveFile));
// WAVE header
// see http://ccrma.stanford.edu/courses/422/projects/WaveFormat/
writeString(output, "RIFF"); // chunk id
writeInt(output, 36 + rawData.length); // chunk size
writeString(output, "WAVE"); // format
writeString(output, "fmt "); // subchunk 1 id
writeInt(output, 16); // subchunk 1 size
writeShort(output, (short) 1); // audio format (1 = PCM)
writeShort(output, (short) 1); // number of channels
writeInt(output, SAMPLE_RATE); // sample rate
writeInt(output, SAMPLE_RATE * 2); // byte rate
writeShort(output, (short) 2); // block align
writeShort(output, (short) 16); // bits per sample
writeString(output, "data"); // subchunk 2 id
writeInt(output, rawData.length); // subchunk 2 size
// Audio data (conversion big endian -> little endian)
short[] shorts = new short[rawData.length / 2];
ByteBuffer.wrap(rawData).order(ByteOrder.LITTLE_ENDIAN).asShortBuffer().get(shorts);
ByteBuffer bytes = ByteBuffer.allocate(shorts.length * 2);
for (short s : shorts) {
//Apply Gain
s *= iGain;
if(s>32767)
{
s=32767;
}
else if(s<-32768)
{
s=-32768;
}
bytes.putShort(s);
}
output.write(bytes.array());
} finally {
if (output != null) {
output.close();
}
}
}
private File getFile(final String suffix) {
Time time = new Time();
time.setToNow();
return new File(Environment.getExternalStorageDirectory(), time.format("%Y%m%d%H%M%S") + "." + suffix);
}
private void writeInt(final DataOutputStream output, final int value) throws IOException {
output.write(value >> 0);
output.write(value >> 8);
output.write(value >> 16);
output.write(value >> 24);
}
private void writeShort(final DataOutputStream output, final short value) throws IOException {
output.write(value >> 0);
output.write(value >> 8);
}
private void writeString(final DataOutputStream output, final String value) throws IOException {
for (int i = 0; i < value.length(); i++) {
output.write(value.charAt(i));
}
}
}
声音非常低 寻找解决方案如何应用增益变化