Delta Encoding - Simple Example

Simple Example

Perhaps the simplest example is storing values of bytes as differences (deltas) between sequential values, rather than the values themselves. So, instead of 2, 4, 6, 9, 7, we would store 2, 2, 2, 3, −2. This is not very useful when used alone, but it can help further compression of data in which sequential values occur often. IFF 8SVX sound format applies this encoding to raw sound data before applying compression to it. Unfortunately, not even all 8-bit sound samples compress better when delta encoded, and the usability of delta encoding is even smaller for 16-bit and better samples. Therefore, compression algorithms often choose to delta encode only when the compression is better than without. However, in video compression delta frames can considerably reduce frame size, and are used in virtually every video compression codec.