Java – Convert byte array to double array

I encountered some problems with WAV files in Java

WAV format: PCM_ Signed 44100.0 Hz, 24 bit, stereo, 6 bytes / frame, small end

>I extract the wav data into a byte array that has no problem. > I'm trying to convert a byte array to a double array, but some double digits have a "Nan" value

Code:

ByteBuffer byteBuffer = ByteBuffer.wrap(byteArray);
double[] doubles = new double[byteArray.length / 8];
for (int i = 0; i < doubles.length; i++) {
    doubles[i] = byteBuffer.getDouble(i * 8);
}

The fact that 16 / 24 / 32 bit, mono / stereo makes me confused

I'm going to pass double [] to the FFT algorithm and get the audio

thank you

Solution

Try this:

public static byte[] toByteArray(double[] doubleArray){
    int times = Double.SIZE / Byte.SIZE;
    byte[] bytes = new byte[doubleArray.length * times];
    for(int i=0;i<doubleArray.length;i++){
        ByteBuffer.wrap(bytes,i*times,times).putDouble(doubleArray[i]);
    }
    return bytes;
}

public static double[] toDoubleArray(byte[] byteArray){
    int times = Double.SIZE / Byte.SIZE;
    double[] doubles = new double[byteArray.length / times];
    for(int i=0;i<doubles.length;i++){
        doubles[i] = ByteBuffer.wrap(byteArray,times).getDouble();
    }
    return doubles;
}

public static byte[] toByteArray(int[] intArray){
    int times = Integer.SIZE / Byte.SIZE;
    byte[] bytes = new byte[intArray.length * times];
    for(int i=0;i<intArray.length;i++){
        ByteBuffer.wrap(bytes,times).putInt(intArray[i]);
    }
    return bytes;
}

public static int[] toIntArray(byte[] byteArray){
    int times = Integer.SIZE / Byte.SIZE;
    int[] ints = new int[byteArray.length / times];
    for(int i=0;i<ints.length;i++){
        ints[i] = ByteBuffer.wrap(byteArray,times).getInt();
    }
    return ints;
}