METHOD AND APPARATUS FOR TRANSFORMING IMAGES, AND METHOD AND APPARATUS FOR INVERSELY TRANSFORMING IMAGES

摘要

Disclosed are a method and apparatus for transforming images and a method and apparatus for inversely transforming images. According to the present invention, trigonometric-function-based values, from among the values of elements of an NxN transform matrix used in the one-dimensional discrete cosine transform of a block having a size of NxN, are substituted with values of predetermined rational numbers, and the block having the size of NxN is transformed using the matrix having the substituted values.