Audio recorder

여러가지 예제 프로그램을 이용해봤으나, 나의 앱 구조상 성공한 건 아래의 code. 

참고로 Fragment 액티비티에서 ExtAudioRecorder(오디오 레코딩) 액티비티를 사용하는 구조이다.

MainActivity.java : 메인 액티비티 (프래그먼트를 위한 껍데기)

Fragment.java : 프래그먼트 액티비티

ExtAudioRecorder.java : 오디오 레코딩 액티비티

Fragment.java

public class Q11Fragment extends Fragment implements View.OnClickListener{     private ExtAudioRecorder extAudioRecorder;       public static Fragment newInstance() {         Fragment fragment = new Fragment();         return fragment;     }     public Fragment() {         // Required empty public constructor     }     @Override     public void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);     }     @Override     public View onCreateView(LayoutInflater inflater, ViewGroup container,                              Bundle savedInstanceState) {         View view = inflater.inflate(R.layout.fragment, container, false);         Button tv1 = (Button) view.findViewById(R.id.button_start);         tv1.setOnClickListener(this);         Button tv2 = (Button) view.findViewById(R.id.button_stop);         tv2.setOnClickListener(this);         Button tv3 = (Button) view.findViewById(R.id.button_play);         tv3.setOnClickListener(this);         Button tv4 = (Button) view.findViewById(R.id.button_play_ext);         tv4.setOnClickListener(this);         // Inflate the layout for this fragment         return view;     }     @Override     public void onClick(View v) {         switch (v.getId()) {             //녹음시작             case R.id.button_start:                 extAudioRecorder = ExtAudioRecorder.getInstanse(true);                 extAudioRecorder.setOutputFile(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS) + "/test_record.mp3");                 extAudioRecorder.getMaxAmplitude();                 extAudioRecorder.prepare();                 extAudioRecorder.start();                 break;             //녹음종료             case R.id.button_stop:                 extAudioRecorder.stop();                 extAudioRecorder.release();                 break;             //녹음내용 플레이             case R.id.button_play:                 extAudioRecorder = ExtAudioRecorder.getInstanse(true);                 extAudioRecorder.getMaxAmplitude();                 extAudioRecorder.prepare();                 extAudioRecorder.release();                 extAudioRecorder.play(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS) + "/test_record.mp3");                 break;             // 외부 파일 플레이 테스트용             case R.id.button_play_ext:                 extAudioRecorder = ExtAudioRecorder.getInstanse(true);                 extAudioRecorder.getMaxAmplitude();                 extAudioRecorder.prepare();                 extAudioRecorder.release();                 extAudioRecorder.play(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS) + "/beep1.mp3");                 break;         }     } }

AndroidManifest.xml (</application> 밑에 아래 세 줄 추가)   

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>     <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>     <uses-permission android:name="android.permission.RECORD_AUDIO"></uses-permission>

ExtAudioRecorder.java (해외 사이트가 출처인데, 어디인지 잊어버렸다...-_-;; 기존출처 내용에 Play 메소드만 추가하였다.)

public class ExtAudioRecorder {     private final static int[] sampleRates = {44100, 22050, 11025, 8000};     private MediaPlayer player;     String RECORDED_FILE = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS) + "/test_record.mp3";     public static ExtAudioRecorder getInstanse(Boolean recordingCompressed)     {         ExtAudioRecorder result = null;         if(recordingCompressed)         {             result = new ExtAudioRecorder( false,                     AudioSource.MIC,                     sampleRates[3],                     AudioFormat.CHANNEL_IN_STEREO,                     AudioFormat.ENCODING_PCM_16BIT);         }         else         {             int i=0;             do             {                 result = new ExtAudioRecorder( true,                         AudioSource.MIC,                         sampleRates[i],                         AudioFormat.CHANNEL_IN_STEREO,                         AudioFormat.ENCODING_PCM_16BIT);             } 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()     {         public void onPeriodicNotification(AudioRecord recorder)         {             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();             }         }         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(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(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                         randomAccessWriter = new RandomAccessFile(filePath, "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");                 }                 (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(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;                 audioRecorder.startRecording();                 audioRecorder.read(buffer, 0, buffer.length);             }             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();                 }                 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;         }     }     public void play(String path_Q11){         if (player != null) {             player.stop();             player.release();             player = null;         }         //Toast.makeText(getApplicationContext(), "녹음된 파일을 재생합니다.", Toast.LENGTH_LONG).show();         try {             player = new MediaPlayer ();             player.setDataSource(path_Q11);             player.prepare();             player.start();         } catch (Exception e) {             Log.e("SampleAudioRecorder", "Audio play failed.", e);         }     }     /*      *      * Converts a byte[2] to a short, in LITTLE_ENDIAN format      *      */     private short getShort(byte argB1, byte argB2)     {         return (short)(argB1 | (argB2 << 8));     } }