Question

I wanted to manipulate the image by playing with the pixel bits. So, I wanted to covert the pixels I grabbed from PixelGrabber. The argb value were in bytes. Now I want to convert array of bytes into bits and manipulate it. And then convert back to bytes array.

For Example:
-1057365 into 11101111 11011101 10101011 11111111 and
11101111 11011101 10101011 11111111 into -1057365

Anyone know there’s any efficient way to converting between them? Or java has method implemented for it and I don’t know.

Thx for helping.

Answer 1

You might want to take a look at BitSet.

byte[] argb = ...
BitSet bits = BitSet.valueOf(argb);
bits.set(0); // sets the 0th bit to true
bits.clear(0); // sets the 0th bit to false

byte[] newArgb = bits.toByteArray();

/edit
To convert a byte[] to an int:

int i = 0;
for(byte b : newArgb) { // you could also omit this loop
    i <<= 8;            // and do this all on one line
    i |= (b & 0xFF);    // but it can get kind of messy.
}

or

ByteBuffer bb = ByteBuffer.allocate(4);
bb.put(newArgb);
int i = bb.getInt();