METHOD AND APPARATUS FOR ENCODING AND DECODING IMAGE USING ROTATIONAL TRANSFORM

摘要

FIELD: information technology.SUBSTANCE: method of encoding images involves generating a first frequency coefficient matrix by transforming a predetermined block to a frequency domain; determining whether the first frequency coefficient matrix includes coefficients whose absolute values are greater than a predetermined value; generating a second frequency coefficient matrix by selectively partially switching at least one of rows and columns of the first frequency coefficient matrix according to an angle parameter based on the determination result; and selectively encoding the second frequency coefficient matrix based on the determination result.EFFECT: high compression ratio when encoding a frequency coefficient matrix.15 cl, 21 dwg