【发布时间】：2010-05-10 08:47:05
【问题描述】：
我想在安卓手机上开发一个关于录音机的应用程序。我必须录制大约 30 秒的声音，然后停止并将录制的声音保存在画廊中。有的话可以发一下代码吗？
【问题讨论】：
【发布时间】：2010-05-10 08:47:05
【问题描述】：
有an example of how to do audio capture using MediaRecorder in the Android Developer Documentation。
我建议将文件保存在 SD 卡上，然后让您的图库代码检查 SD 卡以查看要显示的文件。您可以使用Environment.getExternalStorageDirectory() method 获取 SD 卡的目录。最好将文件保存在 SD 卡根目录的子目录中。
确保您give your applications the Permissions it will need。至少它需要RECORD_AUDIO 和WRITE_EXTERNAL_STORAGE。
【讨论】：
输出：
MainActivity.java：
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.widget.Button;
/**
* This class shows how to run Sound Recorder activity
* @author The Developer's Info
*/
public class Main extends Activity {
private static final int REQUEST_CODE_RECORD = 0;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button startRecording = (Button) findViewById(R.id.startBtn);
startRecording.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent recordIntent = new Intent(
MediaStore.Audio.Media.RECORD_SOUND_ACTION);
startActivityForResult(recordIntent, REQUEST_CODE_RECORD);
}
});
}
}
main.xml：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<Button
android:id="@+id/startBtn"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/startBtnText" />
</LinearLayout>
【讨论】：
如果你想录制清晰的声音你应该使用录音机...
录音机实现如下..
public static int datacount=1;
private static final int RECORDER_BPP = 16;
private static final String AUDIO_RECORDER_FILE_EXT_WAV = ".wav";
private static final String AUDIO_RECORDER_FOLDER = "/'/'";
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_STEREO;
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;
int numCrossing,p;
public int frequency;
public static File myfile;
private Context mcontext;
public static String final_sound_path=null;
Handler handler;
public static String filename;
public Taukyrecorder(Context cntxt) {
// TODO Auto-generated constructor stub
mcontext=cntxt;
handler=new Handler();
wave=new Taukywave(mcontext);
bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,RECORDER_CHANNELS,RECORDER_AUDIO_ENCODING);
recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
RECORDER_SAMPLERATE, RECORDER_CHANNELS,RECORDER_AUDIO_ENCODING, bufferSize);
recorder.setRecordPositionUpdateListener(new OnRecordPositionUpdateListener() {
@Override
public void onPeriodicNotification(AudioRecord recorder) {
// TODO Auto-generated method stub
}
@Override
public void onMarkerReached(AudioRecord recorder) {
// TODO Auto-generated method stub
}
}, handler);
}
//Get the file for saving sound into the folder
public File GetFileTOwriteSound()
{
File tempPicFile=null;
String ext_storage_state=Environment.getExternalStorageState();
File mediaStorage=new File(Environment.getExternalStorageDirectory()+"/TAUKY/SOUNDS");
if(ext_storage_state.equalsIgnoreCase(Environment.MEDIA_MOUNTED))
{
if(!mediaStorage.exists())
{
mediaStorage.mkdirs();
}else
{
//do nothing
}
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss")
.format(new Date());
tempPicFile = new File(mediaStorage.getPath() + File.separator
+ "SOUND_" + timeStamp + ".wav");
myfile=tempPicFile;
}
else
{
Toast.makeText(mcontext, "NO SDCARD MOUNTED", 1).show();
}
return tempPicFile;
}
public 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);
}
public void startRecording(){
recorder.startRecording();
isRecording = true;
recordingThread = new Thread(new Runnable() {
@Override
public void run() {
writedataToFile();
}
},"AudioRecorder Thread");
recordingThread.start();
}
private void writedataToFile(){
final byte data[] = new byte[bufferSize];
filename = getTempFilename();
FileOutputStream os = null;
try {
os = new FileOutputStream(filename);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if(null != os){
while(isRecording){
read = recorder.read(data, 0, bufferSize);
wave.Updatewave(data);
// new Thread(new Runnable() {
//
// @Override
// public void run() {
// // TODO Auto-generated method stub
//
// for (int i = 0; i < read; i++) {
//
// sum +=data [i] * data [i];
// }
// if (read> 0) {
// final double amplitude = sum / read;
// //pb.setProgress((int) Math.sqrt(amplitude));
//
// wave.Updatewave(amplitude);
// }
//
//
//
// }
// }).start();
Log.i("recorder", "Recording");
if(AudioRecord.ERROR_INVALID_OPERATION != read){
try {
os.write(data);
//
} catch (IOException e) {
e.printStackTrace();
}
numCrossing=0; //initialize your number of zero crossings to 0
for (p=0;p<bufferSize/4;p+=4) {
if (data[p]>0 && data[p+1]<=0) numCrossing++;
if (data[p]<0 && data[p+1]>=0) numCrossing++;
if (data[p+1]>0 && data[p+2]<=0) numCrossing++;
if (data[p+1]<0 && data[p+2]>=0) numCrossing++;
if (data[p+2]>0 && data[p+3]<=0) numCrossing++;
if (data[p+2]<0 && data[p+3]>=0) numCrossing++;
if (data[p+3]>0 && data[p+4]<=0) numCrossing++;
if (data[p+3]<0 && data[p+4]>=0) numCrossing++;
}//for p
for (p=(bufferSize/4)*4;p<bufferSize-1;p++) {
if (data[p]>0 && data[p+1]<=0) numCrossing++;
if (data[p]<0 && data[p+1]>=0) numCrossing++;
}
frequency=(8000/bufferSize)*(numCrossing/2); // Set the audio Frequency to half the number of zero crossings, times the number of samples our buffersize is per second.
handler.post(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
//view.setText("Frequency is"+frequency);
}
});
}
}
try {
os.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
public void stopRecording(){
String getfilename=GetFileTOwriteSound().getAbsolutePath();
final_sound_path=getfilename;
if(null != recorder){
isRecording = false;
recorder.stop();
recorder.release();
recorder = null;
recordingThread = null;
}
copyWaveFile(getTempFilename(),getfilename);
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 = 2;
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 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) (2 * 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);
}
}
【讨论】：
所以您希望有人实际发布应用程序的全部代码您想要编码？
Here it is，我猜。
【讨论】：
您可以编写实际的录音代码，也可以利用手机中现有的录音机应用程序......大多数手机都有一个默认的录音机应用程序......
使用相应的操作调用 startActivityForResult。以下是代码。
Intent recordIntent = new Intent(MediaStore.Audio.Media.RECORD_SOUND_ACTION);
startActivityForResult(recordIntent, REQUEST_CODE_RECORD);
【讨论】：