Efficient Coding of the Classification Table in Low Bit Rate Subband Image Coding by Use of Hierarchical Enumeration

A new method for lossless coding of the classiication table in low bit rate subband image coders with block-wise classiication is proposed. The method is referred to as hierarchical enumeration and uses an algorithmic enumeration technique to associate a xed-length unique binary code-word with each possible combination of integers deening the classiication table. The resulting bit rate is less than the rst order entropy of the classiication table. When using hierarchical enumeration in combination with pyramid vector quantization of the subband samples, a high performance image coder using only xed-length codewords is obtained. The proposed coder compares favorably with state-of-the art image coders using variable-length coding.