bijection

I need an algorithm that can do a one-to-one mapping (ie. no collision) of a 32-bit signed integer onto another 32-bit signed integer. My real concern is enough entropy so that the output of the function appears to be random. Basically I am looking for a cipher similar to XOR Cipher but that can generate more arbitrary-looking outputs. Security is not my real concern, although obscurity is. Edit for clarification purpose: The algorithm must be symetric, so that I can reverse the operation without a keypair. The algorithm must be bijective, every 32-bit input number must generate a 32-bit