Patent ID: 7724821

Claim:
A video decoder comprising: a receiver which receives a compressed video signal, the compressed video signal containing variable length coded data representing a set of video spatial frequency coefficients of an individual sub-block using a scanning pattern of a plurality of scanning patterns, the scanning pattern scanning each of a plurality of sub-blocks having n X n coefficients, in the following sequence: M(0,0), M(1,0), M(0,1), M(0,2), M(1,1), M(2,0), M(3,0), M(2,1), M(1,2), . . . , M(n−1, n−1) from lowest frequency to highest frequency to produce a set of reordered coefficients, and containing a scanning mode signal indicating the scanning pattern, the scanning mode signal not being variable coded; a demultiplexer which extracts the variable length coded data and the scanning mode signal from the received compressed video signal; a variable length decoder which decodes the variable length coded data; a scanner which scans the variable length decoded data according to the scanning pattern of the plurality of scanning patterns based on the scanning mode signal to generate scanned data; a decoder which decodes the scanned data by dequantization and inverse transform.