Arithmetic coding-an alternative VLC strategy for video coding

Variable length coding (VLC), otherwise known as entropy coding, is often used to achieve maximum compression from a video codec. The technique attempts to exploit any residual correlation exhibited by the coded data following the application of a data compression algorithm. Traditional VLC techniques employing prefix (eg Huffman) coding are examined and the compression limit achievable with such schemes is highlighted. The paper then presents an overview of arithmetic coding, in particular Binary Arithmetic Coding (BAC): it introduces a number of basic concepts and considers, with the aid of an example, both the coding and decoding algorithms