Arithmetic Codes for Image Coding: Their Advantages and the Effort to Make Them Practical

抄録

The arithmetic code has come to be used for image coding about 40 years ago. It was first adopted in bi-level image coding standard and nowadays widely adopted in multi-level image coding and video coding standards. Arithmetic code is classified as a non-block code in the information theory, and quite powerful by its ability and robustness for various target images. In this paper, its largest advantage for coding multi-context sources is described by comparing with the case using block codes. Additional advantage of arithmetic coding is its robustness based on the affinity with statistic learning. Therefore, the separation of model and entropy coding can be easily done and the current context and the observed symbol are enough for applying an arithmetic coding, while code set design and selection rule from the plural codes will be required in Huffman coding. Also, there were various efforts to make the arithmetic codes practical by referring to the designing parameters of known code including MELCODE.