Image transformation method, Reverse image transformation method and Reverse image transformation apparatus

摘要

method for image transformation, method for inverse image transformation and apparatus for inverse image transformation. a method for image processing, an image processing apparatus, a method for reverse image processing, and a reverse image processing apparatus, the method for image transformation including the operations of selecting a predetermined frequency area for image processing. frequency relative to an input block mxn (where m and n are positive integers), obtaining a truncated transformation matrix, selecting elements for generating transformation coefficients corresponding to the frequency area selected from elements of an mxn transformation matrix for use frequency transformation with respect to input block mxn for use in frequency transformation with respect to input block mxn, and producing transformation coefficients corresponding to the selected frequency area by performing frequency transformations by applying to the truncated transformation matrix mxn the input block.