METHOA AND APPARATUS FOR TRANSFORMING IMAGE, AND METHOD AND APPARATUS FOR INVERSE-TRANSFORMING IMAGE

摘要

PURPOSE: An image transforming method, an image transforming device thereof, an inverse transforming method thereof, and an inverse transforming device thereof are provided to reduce the computational complexity spent in a transformation and inverse transformation process. CONSTITUTION: A frequency domain selecting unit selects a fixed frequency domain for transforming the frequency of an MxN input block. A reduction transformation matrix acquiring unit selects elements from the elements of an MxN transformation matrix to generate a transformation coefficient for a selected frequency domain. A frequency transforming unit applies a reduced transformation matrix to the MxN input block(720). The frequency transforming unit generates the transformation coefficient corresponding to the selected frequency domain(730).