Process and circuit for block matching in two-dimensional picture signals

Abstract

For processing data signals representative of pixels, each of the pictures s scanned, column per column in successive horizontal bands each having a height equal to an entire fraction of the height of the picture, whereby a representation of the picture as pixels distributed in rows and columns is obtained, each band having a common predetermined number of rows. The picture is fractionated into mutually adjacent blocks of pixels each having M pixels in each of N mutually adjacent columns, M and N being predetermined integers and M being a simple multiple of the number of pixels in one column of a band and N being a whole fraction of the number of colums per image. For each of the blocks of the current picture in turn, the block is compared with each of a plurality of blocks of the same size in a search window of L columns of H pixels in the preceding image, L and H being predetermined integers greater than M and respectively the window containing the block of the current picture and the computaton being carried out in M*M cycles, namely in the time required for scanning the block of the current image, by parallel computation, during each cycle of all partial distortions between each pixel of the current block and each of the pixels corresponding thereto upon each possible offset of the block in the search window of the preceding picture. Then the best match is determined as the correspondence having the least distortion.