Patent ID: 7327290

Claim:
An image-decoding system for processing a plurality of data coefficients in a data stream composed of a plurality of portions, the image-decoding system comprising: a decoding unit, reading the data coefficients in each portion, respectively; an address generator coupled to the decoding unit, figuring out a logical address of a codeword corresponding to the data coefficients and figuring out a physical address of the codeword corresponding to the data coefficients to allow the decoding unit to locate the codeword corresponding to the data coefficients based on the logical address and the physical address of the codeword; and a memory unit coupled to the decoding unit and the address generator, storing the codeword and the data coefficients; wherein the decoding unit determines run length of the data coefficients to generate run length information according to the codeword, computes the amplitude of the data coefficients based on the run length information, and writes the computed data coefficients into the memory unit according to the physical address to update the data coefficients in the memory unit during a first scan mode, and the decoding unit further refines the updated data coefficients according to the run length information generated during the first scan mode if the decoding unit changes from the first scan mode to a second scan mode in order to increase the speed performance of the image-decoding system.