Patent ID: 6842483

Claim:
A method of selecting, for a first block of a first image based on an array of pixels, a similar block of a second image based on said array of pixels, the method including: (i) defining a reference pixel in said array; (ii) deriving at least one threshold value based on a previously-derived mismatch value for at least one further block of the first image; (iii) defining a plurality of search zones in said array, labelled by integer index i, said zones surrounding said reference pixel and having a radius which increases for increasing i; (iv) after step (ii), for successive zones, and for successive pixels in each zone, determining a block of the second image based on each successive pixel of said successive pixels, and determining a mismatch value between said first block of the first image and said determined block based on a mismatch criterion; and (v) selecting said similar block of the second image as the determined block for which said determined mismatch is lowest; wherein step (iv) is terminated upon at least one termination criterion being satisfied, said termination criterion being defined in terms of a respective said threshold value based on a previously-derived mismatch value.