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I want to create .wav file so i can play it later if needed but AudioRecord(i need to use AudioRecord) only sends me data in raw format. So i tried adding .wav header in my file like other answers suggested but i can't seem to make it work, what am i doing wrong?

this is my method which saves temporary file with .raw extension:

 private void onWriteAudioDataToFile(int index, short[] sData) {
    String filename = getFilename(index, false);
    FileOutputStream os;
    try {
        os = new FileOutputStream(filename);
        byte bData[] = short2byte(sData);
        os.write(bData);
    } catch (Exception e) {
        e.printStackTrace();
    }
    copyWaveFile(getFilename(index, false), getFilename(index, true));
}

this is the method that reads that file and converts it to .wav format by adding header:

private void copyWaveFile(String inFilename, String outFilename) {
    int channels = 2;
    long byteRate = 16 * 44100 * channels / 8;
    long longSampleRate = 44100;

    FileInputStream in;
    FileOutputStream out;
    long totalAudioLen;
    long totalDataLen;

    byte[] data = new byte[bufferSize];

    try {
        in = new FileInputStream(inFilename);
        out = new FileOutputStream(outFilename);
        totalAudioLen = in.getChannel().size();
        totalDataLen = totalAudioLen + 36;

        WriteWaveFileHeader(out, totalAudioLen, totalDataLen,
                longSampleRate, channels, byteRate);

        while (in.read(data) != -1) {
            out.write(data);
        }

        in.close();
        out.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

and the last, if necessary, this is the method for adding header:

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] = 16;  // 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);
}
Mate Križanac
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1 Answers1

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Most common wave format is PCM. The android.media.AudioRecord supports PCM output. You only need to write this to a file then. Taken from how to record .wav format file in android

Community
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Bhargav
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  • it also says "After the file you then create you must program your own converter to wave (or look for an online library for that)." and i am trying to do exactly that, but for some reason it's not working – Mate Križanac Aug 18 '15 at 11:47
  • Have a look at this http://stackoverflow.com/questions/9179536/writing-pcm-recorded-data-into-a-wav-file-java-android – Bhargav Aug 18 '15 at 11:50