我在市场上有一个使用 AudioRecord 类录制音频并将其保存到 SD 卡的应用程序。使用新 HTC One 系列手机的用户无法录制。
开始录制时，它会在 SD 卡中保存一个 1kb 的文件，然后停止。通常它至少会创建一个 44KB 的标头，所以我相信它会在 prepare() 函数的某个地方停止。我没有 HTC 来测试这个，所以我傻眼了。我附上了我用来录制的课程，我正在录制未压缩的音频。在我的记录活动中，我使用构造函数初始化 extAudioRecorder 对象，如下所示：
extAudioRecorder = new ExtAudioRecorder(true,
AudioSource.MIC,
44100,
AudioFormat.CHANNEL_IN_MONO,
AudioFormat.ENCODING_PCM_16BIT);
我觉得这应该适用于较新的手机。
任何帮助，将不胜感激。这是我用于录制的课程的完整来源。它也可能对 LG Optimus One 手机做同样的事情。
public class ExtAudioRecorder implements Runnable
{
private final static int[] sampleRates = {44100, 22050, 11025, 8000};
private static final String AUDIO_RECORDER_FOLDER = "FOLDER";
String sdPath = Environment.getExternalStorageDirectory().getPath();
File file = new File(sdPath,AUDIO_RECORDER_FOLDER);
String FullFilePath;
String fileName;
static int sampleRate;
private volatile boolean recording = false;
double RecordReadDelayInSeconds = 0;
double RecordDelayInSeconds = 0;
private MediaPlayer mPlayer;
private static String mp3Path = Environment.getExternalStorageDirectory() + "/FOLDER/tmp/tmp.mp3";
double beatDelayInSeconds = 0;
public ExtAudioRecorder getInstanse(Boolean recordingCompressed)
{
ExtAudioRecorder result = null;
if(recordingCompressed)
{
result = new ExtAudioRecorder( false,
AudioSource.MIC,
sampleRates[3],
AudioFormat.CHANNEL_IN_MONO,
AudioFormat.ENCODING_PCM_16BIT);
}
else
{
int i=0;
do
{
result = new ExtAudioRecorder( true,
AudioSource.MIC,
sampleRates[i],
AudioFormat.CHANNEL_IN_MONO,
AudioFormat.ENCODING_PCM_16BIT);
sampleRate = sampleRates[i];
} while((++i<sampleRates.length) & !(result.getState() == ExtAudioRecorder.State.INITIALIZING));
}
return result;
}
/**
* INITIALIZING : recorder is initializing;
* READY : recorder has been initialized, recorder not yet started
* RECORDING : recording
* ERROR : reconstruction needed
* STOPPED: reset needed
*/
public enum State {INITIALIZING, READY, RECORDING, ERROR, STOPPED};
public static final boolean RECORDING_UNCOMPRESSED = true;
public static final boolean RECORDING_COMPRESSED = false;
// The interval in which the recorded samples are output to the file
// Used only in uncompressed mode
private static final int TIMER_INTERVAL = 120;
// Toggles uncompressed recording on/off; RECORDING_UNCOMPRESSED / RECORDING_COMPRESSED
private boolean rUncompressed;
// Recorder used for uncompressed recording
private AudioRecord audioRecorder = null;
// Recorder used for compressed recording
private MediaRecorder mediaRecorder = null;
// Stores current amplitude (only in uncompressed mode)
private int cAmplitude= 0;
// Output file path
private String filePath = null;
// Recorder state; see State
private State state;
// File writer (only in uncompressed mode)
private RandomAccessFile randomAccessWriter;
// Number of channels, sample rate, sample size(size in bits), buffer size, audio source, sample size(see AudioFormat)
private short nChannels;
private int sRate;
private short bSamples;
private int bufferSize;
private int aSource;
private int aFormat;
// Number of frames written to file on each output(only in uncompressed mode)
private int framePeriod;
// Buffer for output(only in uncompressed mode)
private byte[] buffer;
// Number of bytes written to file after header(only in uncompressed mode)
// after stop() is called, this size is written to the header/data chunk in the wave file
private int payloadSize;
/**
*
* Returns the state of the recorder in a RehearsalAudioRecord.State typed object.
* Useful, as no exceptions are thrown.
*
* @return recorder state
*/
public State getState()
{
return state;
}
/*
*
* Method used for recording.
*
*/
private AudioRecord.OnRecordPositionUpdateListener updateListener = new AudioRecord.OnRecordPositionUpdateListener()
{
@Override
public void onPeriodicNotification(AudioRecord recorder)
{
if (state != State.STOPPED)
{
audioRecorder.read(buffer, 0, buffer.length); // Fill buffer
try
{
randomAccessWriter.write(buffer); // Write buffer to file
payloadSize += buffer.length;
if (bSamples == 16)
{
for (int i=0; i<buffer.length/2; i++)
{ // 16bit sample size
short curSample = getShort(buffer[i*2], buffer[i*2+1]);
if (curSample > cAmplitude)
{ // Check amplitude
cAmplitude = curSample;
}
}
}
else
{ // 8bit sample size
for (int i=0; i<buffer.length; i++)
{
if (buffer[i] > cAmplitude)
{ // Check amplitude
cAmplitude = buffer[i];
}
}
}
}
catch (IOException e)
{
Log.e(ExtAudioRecorder.class.getName(), "Error occured in updateListener, recording is aborted");
stop();
}
}
}
@Override
public void onMarkerReached(AudioRecord recorder)
{
// NOT USED
}
};
/**
*
*
* Default constructor
*
* Instantiates a new recorder, in case of compressed recording the parameters can be left as 0.
* In case of errors, no exception is thrown, but the state is set to ERROR
*
*/
public ExtAudioRecorder(boolean uncompressed, int audioSource, int sampleRate, int channelConfig, int audioFormat)
{
try
{
rUncompressed = uncompressed;
if (rUncompressed)
{ // RECORDING_UNCOMPRESSED
if (audioFormat == AudioFormat.ENCODING_PCM_16BIT)
{
bSamples = 16;
}
else
{
bSamples = 8;
}
if (channelConfig == AudioFormat.CHANNEL_IN_MONO)
{
nChannels = 1;
}
else
{
nChannels = 2;
}
aSource = audioSource;
sRate = sampleRate;
aFormat = audioFormat;
framePeriod = sampleRate * TIMER_INTERVAL / 1000;
bufferSize = framePeriod * 2 * bSamples * nChannels / 8;
if (bufferSize < AudioRecord.getMinBufferSize(sampleRate, channelConfig, audioFormat))
{ // Check to make sure buffer size is not smaller than the smallest allowed one
bufferSize = AudioRecord.getMinBufferSize(sampleRate, channelConfig, audioFormat);
// Set frame period and timer interval accordingly
framePeriod = bufferSize / ( 2 * bSamples * nChannels / 8 );
Log.w(ExtAudioRecorder.class.getName(), "Increasing buffer size to " + Integer.toString(bufferSize));
}
audioRecorder = new AudioRecord(audioSource, sampleRate, channelConfig, audioFormat, bufferSize);
if (audioRecorder.getState() != AudioRecord.STATE_INITIALIZED)
throw new Exception("AudioRecord initialization failed");
audioRecorder.setRecordPositionUpdateListener(updateListener);
audioRecorder.setPositionNotificationPeriod(framePeriod);
} else
{ // RECORDING_COMPRESSED
mediaRecorder = new MediaRecorder();
mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
}
cAmplitude = 0;
filePath = null;
state = State.INITIALIZING;
} catch (Exception e)
{
if (e.getMessage() != null)
{
Log.e(ExtAudioRecorder.class.getName(), e.getMessage());
}
else
{
Log.e(ExtAudioRecorder.class.getName(), "Unknown error occured while initializing recording");
}
state = State.ERROR;
}
}
/**
* Sets output file path, call directly after construction/reset.
*
* @param output file path
*
*/
public void setOutputFile(String argPath)
{
try
{
if (state == State.INITIALIZING)
{
filePath = argPath;
if (!rUncompressed)
{
mediaRecorder.setOutputFile(sdPath + "/FOLDER/" + filePath);
}
}
}
catch (Exception e)
{
if (e.getMessage() != null)
{
Log.e(ExtAudioRecorder.class.getName(), e.getMessage());
}
else
{
Log.e(ExtAudioRecorder.class.getName(), "Unknown error occured while setting output path");
}
state = State.ERROR;
}
}
/**
*
* Returns the largest amplitude sampled since the last call to this method.
*
* @return returns the largest amplitude since the last call, or 0 when not in recording state.
*
*/
public int getMaxAmplitude()
{
if (state == State.RECORDING)
{
if (rUncompressed)
{
int result = cAmplitude;
cAmplitude = 0;
return result;
}
else
{
try
{
return mediaRecorder.getMaxAmplitude();
}
catch (IllegalStateException e)
{
return 0;
}
}
}
else
{
return 0;
}
}
/**
*
* Prepares the recorder for recording, in case the recorder is not in the INITIALIZING state and the file path was not set
* the recorder is set to the ERROR state, which makes a reconstruction necessary.
* In case uncompressed recording is toggled, the header of the wave file is written.
* In case of an exception, the state is changed to ERROR
*
*/
public void prepare()
{
try
{
if (state == State.INITIALIZING)
{
if (rUncompressed)
{
if ((audioRecorder.getState() == AudioRecord.STATE_INITIALIZED) & (filePath != null))
{
// write file header
if(!file.exists())
file.mkdirs();
fileName = filePath;
FullFilePath = file.getAbsoluteFile() + "/" + fileName;
randomAccessWriter = new RandomAccessFile(FullFilePath, "rw");
randomAccessWriter.setLength(0); // Set file length to 0, to prevent unexpected behavior in case the file already existed
randomAccessWriter.writeBytes("RIFF");
randomAccessWriter.writeInt(0); // Final file size not known yet, write 0
randomAccessWriter.writeBytes("WAVE");
randomAccessWriter.writeBytes("fmt ");
randomAccessWriter.writeInt(Integer.reverseBytes(16)); // Sub-chunk size, 16 for PCM
randomAccessWriter.writeShort(Short.reverseBytes((short) 1)); // AudioFormat, 1 for PCM
randomAccessWriter.writeShort(Short.reverseBytes(nChannels));// Number of channels, 1 for mono, 2 for stereo
randomAccessWriter.writeInt(Integer.reverseBytes(sRate)); // Sample rate
randomAccessWriter.writeInt(Integer.reverseBytes(sRate*bSamples*nChannels/8)); // Byte rate, SampleRate*NumberOfChannels*BitsPerSample/8
randomAccessWriter.writeShort(Short.reverseBytes((short)(nChannels*bSamples/8))); // Block align, NumberOfChannels*BitsPerSample/8
randomAccessWriter.writeShort(Short.reverseBytes(bSamples)); // Bits per sample
randomAccessWriter.writeBytes("data");
randomAccessWriter.writeInt(0); // Data chunk size not known yet, write 0
buffer = new byte[framePeriod*bSamples/8*nChannels];
state = State.READY;
}
else
{
Log.e(ExtAudioRecorder.class.getName(), "prepare() method called on uninitialized recorder");
state = State.ERROR;
}
}
else
{
mediaRecorder.prepare();
state = State.READY;
}
}
else
{
Log.e(ExtAudioRecorder.class.getName(), "prepare() method called on illegal state");
release();
state = State.ERROR;
}
}
catch(Exception e)
{
if (e.getMessage() != null)
{
Log.e(ExtAudioRecorder.class.getName(), e.getMessage());
}
else
{
Log.e(ExtAudioRecorder.class.getName(), "Unknown error occured in prepare()");
}
state = State.ERROR;
}
}
/**
*
*
* Releases the resources associated with this class, and removes the unnecessary files, when necessary
*
*/
public void release()
{
if (state == State.RECORDING)
{
stop();
}
else
{
if ((state == State.READY) & (rUncompressed))
{
try
{
randomAccessWriter.close(); // Remove prepared file
}
catch (IOException e)
{
Log.e(ExtAudioRecorder.class.getName(), "I/O exception occured while closing output file");
}
//delete file
//(new File(filePath)).delete();
}
}
if (rUncompressed)
{
if (audioRecorder != null)
{
audioRecorder.release();
}
}
else
{
if (mediaRecorder != null)
{
mediaRecorder.release();
}
}
}
/**
*
*
* Resets the recorder to the INITIALIZING state, as if it was just created.
* In case the class was in RECORDING state, the recording is stopped.
* In case of exceptions the class is set to the ERROR state.
*
*/
public void reset()
{
try
{
if (state != State.ERROR)
{
release();
filePath = null; // Reset file path
cAmplitude = 0; // Reset amplitude
if (rUncompressed)
{
audioRecorder = new AudioRecord(aSource, sRate, nChannels+1, aFormat, bufferSize);
}
else
{
mediaRecorder = new MediaRecorder();
mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
}
state = State.INITIALIZING;
}
}
catch (Exception e)
{
Log.e(ExtAudioRecorder.class.getName(), e.getMessage());
state = State.ERROR;
}
}
/**
*
*
* Starts the recording, and sets the state to RECORDING.
* Call after prepare().
*
*/
public void start()
{
if (state == State.READY)
{
if (rUncompressed)
{
payloadSize = 0;
RecordReadDelayInSeconds = 0;
RecordDelayInSeconds = 0;
mPlayer = new MediaPlayer();
try {
mPlayer.setDataSource(mp3Path);
mPlayer.prepare();
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SecurityException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
long recordstarted = System.nanoTime();
audioRecorder.startRecording();
long recordstopped = System.nanoTime();
long recordDelay = recordstopped - recordstarted;
double RecordDelayInSeconds = recordDelay / 1000000.0;
Log.i("StartRecording() Delay in seconds", String.valueOf(RecordDelayInSeconds));
long recordreadstarted = System.nanoTime();
audioRecorder.read(buffer, 0, buffer.length);
long recordreadstopped = System.nanoTime();
long recordreadDelay = recordreadstopped - recordreadstarted;
RecordReadDelayInSeconds = recordreadDelay / 1000000.0;
Log.i("Record read() Delay in seconds", String.valueOf(RecordReadDelayInSeconds));
long mediastarted = System.nanoTime();
mPlayer.start();
long mediastopped = System.nanoTime();
long beatDelay = mediastopped - mediastarted;
beatDelayInSeconds = 0;
beatDelayInSeconds = (beatDelay) / 1000000000.0;
Log.i("Beat Delay in seconds", String.valueOf(beatDelayInSeconds));
}
else
{
mediaRecorder.start();
}
state = State.RECORDING;
}
else
{
Log.e(ExtAudioRecorder.class.getName(), "start() called on illegal state");
state = State.ERROR;
}
}
/**
*
*
* Stops the recording, and sets the state to STOPPED.
* In case of further usage, a reset is needed.
* Also finalizes the wave file in case of uncompressed recording.
*
*/
public void stop()
{
if (state == State.RECORDING)
{
if (rUncompressed)
{
audioRecorder.stop();
try
{
randomAccessWriter.seek(4); // Write size to RIFF header
randomAccessWriter.writeInt(Integer.reverseBytes(36+payloadSize));
randomAccessWriter.seek(40); // Write size to Subchunk2Size field
randomAccessWriter.writeInt(Integer.reverseBytes(payloadSize));
randomAccessWriter.close();
//mPlayer.stop();
}
catch(IOException e)
{
Log.e(ExtAudioRecorder.class.getName(), "I/O exception occured while closing output file");
state = State.ERROR;
}
}
else
{
mediaRecorder.stop();
}
state = State.STOPPED;
}
else
{
Log.e(ExtAudioRecorder.class.getName(), "stop() called on illegal state");
state = State.ERROR;
}
}
/*
*
* Converts a byte[2] to a short, in LITTLE_ENDIAN format
*
*/
private short getShort(byte argB1, byte argB2)
{
return (short)(argB1 | (argB2 << 8));
}
public String[] GetFileProperties()
{
String[] fileProperties = new String[3];
fileProperties[0] = FullFilePath;
fileProperties[1] = fileName;
fileProperties[2] = Integer.toString(sampleRate);
return fileProperties;
}
@Override
public void run() {
android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_URGENT_AUDIO);
start();
}
public void StopMediaPlayer()
{
try {
mPlayer.stop();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public boolean isRecording() {
return recording;
}
public int GetSampleRate()
{
return sampleRate;
}
public double GetBeatDelay()
{
return beatDelayInSeconds;
}
public int GetRecordDelay()
{
return (int)(RecordReadDelayInSeconds +RecordDelayInSeconds);
}
}