METHOD AND APPARATUS FOR COMPRESSING IMAGE SIGNAL

摘要

A METHOD OF COMPRESSING IMAGE SIGNALS, TO PROVIDE MORE EFFICIENT COMPRESSION THAN A DISCRETE COSINE TRANSFORM (DCT) WHILE HAVING THE LEAST AMOUNT OF OVERHEAD INFORMATION IS PROVIDED. A PARTIAL EXCHANGE BETWEEN A ROW AND A COLUMN OF A TRANSFORM MATRIX IS PERFORMED BY APPLYING SEVERAL VALUES TO A PARAMETER, WHICH SHOWS AN EXTENT OF PARTIAL EXCHANGE BETWEEN ROWS AND COLUMNS OF THE TRANSFORM MATRIX. WHEN A VALUE OF THE USED ANGLE PARAMETER IS STORED OR TRANSMITTED, AN OVERHEAD INCREASES. PROCESSES GENERATING A RANDOM SEQUENCE OF THE ANGLE PARAMETER, GENERATING A COMPRESSION COEFFICIENT MATRIX REGARDING EACH ANGLE PARAMETER OF THE GENERATED RANDOM SEQUENCE, AND CALCULATING A COMPRESSION RATE ARE REPEATED TO OBTAIN AN ANGLE PARAMETER WITH THE HIGHEST COMPRESSION RATE. THE ANGLE PARAMETER HAVING THE HIGHEST COMPRESSION RATE IS NOT STORED OR TRANSMITTED, BUT A NUMBER IN THE RANDOM SEQUENCE OF THE CORRESPONDING ANGLE PARAMETER IS OBTAINED, AND STORED OR TRANSMITTED.