How to Convert a float array to a byte[2] array and back java

Question

im applying DSP effects to my raw audio input which is in byte[2] array format.To apply DSP i need to convert the byte array to float array and back.To convert byte array to float array i use the following code:

private byte[] buffer;
/*
 * 
 * Converts a byte[2] to a float, in LITTLE_ENDIAN format
 */
private float getFloat(byte argB1, byte argB2) {
    return (float) (argB1 | (argB2 << 8));
}
for (int i = 0; i < N / 2; i++) { 
    curSample[i] = getFloat(buffer[i * 2],
    buffer[i * 2 + 1]);}

I need to convert back curSample(which is a float array) to the byte[2] array.How to do that?

Float is a 32 bit value, how it is so you convert into it from just two bytes? Probably you should use floatToIntBits to convert float into byte array. — Audrius Meškauskas

sr01853 sr01853 · Accepted Answer · 2013-01-25T11:32:19

To convert byte array to float array, what you are doing does not consider the endianness.

int myInt = (byte[0] << 24) |
((byte[1] & 0xff) << 16) |
((byte[2] & 0xff) << 8) |
(byte[3] & 0xff);

or (for little-endian):

int myInt = (byte[3] << 24) |
((byte[2] & 0xff) << 16) |
((byte[1] & 0xff) << 8) |
(byte[0] & 0xff);

Then you can transform to a float using this:

float asFloat = Float.intBitsToFloat(asInt);

To convert it back to byte array

  int j=0;
  byte[] byteArray=new byte[4];
  int data=Float.floatToIntBits(asFloat);
  byteArray[j++]=(byte)(data>>>24);
  byteArray[j++]=(byte)(data>>>16);
  byteArray[j++]=(byte)(data>>>8);
  byteArray[j++]=(byte)(data>>>0);

I also find some similar information here

How to Convert a float array to a byte[2] array and back java

1 Answers