Application of Arithmetic Coding to the Scale Factors in Advanced Audio Coder

The Huffman coding is adopted in MPEG 2 advanced audio coder(AAC) noiseless coding module. However, it is hard to make the probability mode adaptive used in Huffman coding, as well as that the codeword of Huffman can only consist of integer bits. In order to improve the coding efficiency, the arithmetic coding was applied to the scale factors instead of Huffman coding. The experimental results show that high coding efficiency can be achieved when applying the arithmetic coding to the scale factors in AAC.