IMAGE COMPRESSION METHOD USING QUANTIZATION TECHNIQUE USING WAVELET TRANSFORMATION AND SUCCESSIVE APPROXIMATION

摘要

PROBLEM TO BE SOLVED: To minimize a required storage area and to improve image quality by calculating the set of symbols from a coefficient calculated in wavelet transformation, sequencing the set and encoding the symbols which correspond to the context of the symbols included in a band. SOLUTION: A set of k pieces of the symbols is calculated in a step C2 for respective coefficients obtained by the use of wavelet transformation in a step C1. Then they are sequenced and arranged by symbol replacement in a buffer storage area. Here, the encoding of the symbols using arithmetic encoding is performed in a step C3. In this case, in order to improve the appropriateness of encoding, it is required to consider the context of the symbol to be encoded, that is the peripheral part of the symbol 1. This is due to the symbol being encoded can be predicted to a certain degree by semantic contents of the symbol and it is necessary to consider the tree structure of the symbol for performing it.