|| On the Optimality of Binary AIFV Codes with Two Code Trees
||Kengo Hashimoto, Ken-ichi Iwata, University of Fukui, Japan|
||D7-S4-T2: Topics in Source Coding
||Tuesday, 20 July, 23:00 - 23:20
||Tuesday, 20 July, 23:20 - 23:40
Huffman code is the optimal code in the class of uniquely decodable codes in the sense of the average length of codeword when a single code tree can represent the code. This paper defines hierarchical subclasses of noiseless source codes by allowing k-bit decoding delay for positive integer k and clarifies a necessary and sufficient condition for the uniquely decodable codes with k-bit decoding delay. Furthermore, we show that AIFV code is the optimal code in the class of uniquely decodable codes with 2-bit decoding delay when two code trees represent the noiseless source code.