Patent ID: 6349149
Filing Date: 2002-02-19
Classification: H03M,H04N

Abstract:
An image decoding method for extracting a variable length code from compression-coded data, obtaining an event corresponding to said variable length code by using a variable length code table wherein a reference event consisting of Last, Run, Level, is assigned to each reference variable length code, and deriving an output transform coefficient from said event, the method further comprising:judging whether said variable length code includes a control code, and if said variable length code is judged to include no control code, obtaining an event corresponding to said variable length code by using said variable length code table, and, if said variable length code is judged to include said control code, further judging, whether said variable length code includes a second mode code, and if said variable length code is judged to include said second mode code, obtaining an event corresponding to said variable length code by using said variable length code table and then a transformed event is obtained by transforming the Level value of said event corresponding to said variable length code using a predetermined function, and, if said variable length code is judged to include no second mode code, further judging, whether said variable length code includes a third mode code, and if said variable length code is judged to include said third mode code, obtaining an event corresponding to said variable length code by using said variable length code table and then a transformed event is obtained by transforming the Run value of said event corresponding to said variable length code using a predetermined function, and, if said variable length code is judged to include no third mode code, further judging, whether said variable length code includes a first mode code, and if said variable length code is judged to include said first mode code, obtaining an event by subjecting said variable length code to fixed length decoding.