Example usage for android.media AudioRecord read

Introduction

In this page you can find the example usage for android.media AudioRecord read.

Prototype

public int read(@NonNull ByteBuffer audioBuffer, int sizeInBytes, @ReadMode int readMode) 

Source Link

Document

Reads audio data from the audio hardware for recording into a direct buffer.

Usage

From source file:edu.nchu.cs.dmlab.firemap.mjpeg.RecMicToMp3.java

/**
 * Start recording/*from   w w w.  j a v  a  2s .co  m*/
 */
public void start() {
    // just skip if recording has happened
    if (mIsRecording) {
        return;
    }

    new Thread() {
        @Override
        public void run() {
            if (mHandler != null)
                mHandler.sendEmptyMessage(Message.MSG_DIALOG_OPEN);
            android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_URGENT_AUDIO);
            // caculate minimax buffersize
            final int minBufferSize = AudioRecord.getMinBufferSize(mSampleRate, AudioFormat.CHANNEL_IN_MONO,
                    AudioFormat.ENCODING_PCM_16BIT);
            if (minBufferSize < 0) {
                if (mHandler != null) {
                    mHandler.sendEmptyMessage(Message.MSG_ERROR_GET_MIN_BUFFERSIZE);
                }
                return;
            }
            AudioRecord audioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC, mSampleRate,
                    AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT, minBufferSize * 2);
            // PCM buffer size (5sec)
            short[] buffer = new short[mSampleRate * (16 / 8) * 1 * 5]; // SampleRate[Hz] * 16bit * Mono * 5sec
            byte[] mp3buffer = new byte[(int) (7200 + buffer.length * 2 * 1.25)];

            FileOutputStream output = null;
            try {
                output = new FileOutputStream(mFile);
            } catch (FileNotFoundException e) {
                if (mHandler != null) {
                    mHandler.sendEmptyMessage(Message.MSG_ERROR_CREATE_FILE);
                }
                return;
            }

            // Lame init
            SimpleLame.init(mSampleRate, 1, mSampleRate, 32);

            try {
                try {
                    audioRecord.startRecording();
                    mIsRecording = true;
                } catch (IllegalStateException e) {
                    if (mHandler != null) {
                        mHandler.sendEmptyMessage(Message.MSG_ERROR_REC_START);
                    }
                    return;
                }

                try {
                    if (mHandler != null) {
                        mHandler.sendEmptyMessage(Message.MSG_REC_STARTED);
                    }

                    int readSize = 0;
                    while (mIsRecording) {
                        readSize = audioRecord.read(buffer, 0, minBufferSize);
                        if (readSize < 0) {
                            if (mHandler != null) {
                                mHandler.sendEmptyMessage(Message.MSG_ERROR_AUDIO_RECORD);
                            }
                            break;
                            // no data
                        } else if (readSize == 0) {
                            ;
                            // fetch data
                        } else {
                            int encResult = SimpleLame.encode(buffer, buffer, readSize, mp3buffer);
                            if (encResult < 0) {
                                if (mHandler != null) {
                                    mHandler.sendEmptyMessage(Message.MSG_ERROR_AUDIO_ENCODE);
                                }
                                break;
                            }
                            if (encResult != 0) {
                                try {
                                    output.write(mp3buffer, 0, encResult);
                                } catch (IOException e) {
                                    if (mHandler != null) {
                                        mHandler.sendEmptyMessage(Message.MSG_ERROR_WRITE_FILE);
                                    }
                                    break;
                                }
                            }
                        }
                    }
                    int flushResult = SimpleLame.flush(mp3buffer);
                    if (flushResult < 0) {
                        if (mHandler != null) {
                            mHandler.sendEmptyMessage(Message.MSG_ERROR_AUDIO_ENCODE);
                        }
                    }
                    if (flushResult != 0) {
                        try {
                            output.write(mp3buffer, 0, flushResult);
                        } catch (IOException e) {
                            if (mHandler != null) {
                                mHandler.sendEmptyMessage(Message.MSG_ERROR_WRITE_FILE);
                            }
                        }
                    }

                    try {
                        output.close();
                    } catch (IOException e) {
                        if (mHandler != null) {
                            mHandler.sendEmptyMessage(Message.MSG_ERROR_CLOSE_FILE);
                        }
                    }
                } finally {
                    audioRecord.stop();
                    audioRecord.release();
                }
            } finally {
                SimpleLame.close();
                mIsRecording = false;
            }

            if (mHandler != null) {
                mHandler.sendEmptyMessage(Message.MSG_REC_STOPPED);
            }

            // Upload Audio
            uploadVoice();
            if (mHandler != null)
                mHandler.sendEmptyMessage(Message.MSG_DIALOG_CLOSE);
        }
    }.start();
}

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