Coding and decoding methods for a picture signal using overlapping blocks having variable block sizes and apparatuses therefor

Abstract From the Canadian patent

A method of coding and decoding a bidimensional signal, comprising the steps of:, at a coding side (a) dividing a bidimensional input signal into rectangular blocks of a plurality of sizes; (b) providing window functions hAM(m) and hBN(n) on a direction and block size basis;, (c) calculating assuming that a block of interest, has a M X N size transformed signals Xp(k,i) from input signals xp(m, n) (m = 0, 1, ..... 2M-1; n = 0 1, ..... 2N-1) by a transform equation: 2M-1 2N-1, Xp(k, i) = .SIGMA. .SIGMA. xp(m,n) hAM(m) hBN(n) m=0 n=0, x cos{(2m+M+1) (2k+1) .pi./(4M)} x cos{(2n+N+1) (2i+1) .pi./(4N)}, (k = 0 1, ... M-1; i = 0, 1, ... N-1), (d) transmitting block division information and said …