FUNCTIONAL SET COMPRESSION

A method of compressing image data from a set of individual images wherein the images have a correlation between images of approximately greater than 0.5. A wavelet transform is applied to a reference image of the set in order to determine a series of reference coefficients wi(1). The same wavelet transform is applied to an adjacent image of said set in order to determine another series of coefficients wi(2). The series of coefficients wi(k−1) and wi(k) (for all k≧2) are then compared in order to determine a coefficient b(k) and a series of coefficients ci(k), such that wi(k) may be determined from the relationship wi(k)=└b(k)wi(k−1)┘+ci(k). Alternatively, b(k) may be set equal to one rather than be determined. The coefficients for the reference image wi(1), b(k) (if b(k) is not equal to one), and ci(k) are then entropy encoded in order to form a compressed set of image data.