METHOD, DEVICE FOR COMPRESSING IMAGE DATA, METHOD, DEVICE FOR TRANSMITTING/RECEIVING IMAGE DATA AND IMAGE DATA RECEIVER

摘要

PROBLEM TO BE SOLVED: To provide an image with high picture quality on the reception side concerning a desired area without increasing the amount of compressed data. SOLUTION: Before compressing image data A through orthogonal transformation, the unimportant image area of image data A is passed through a low-pass filter(LPF) B and the important image area of image data A is not passed through the LPF B. Concerning output image data C of the LPF B, the amount of transmission data is reduced by reducing the high frequency component of unimportant image area and concerning the important image area, picture quality is improved by increasing the amount of transmission data by the decreased amt. The unimportant image area and important image area are arbitrarily designated by an operator on the reception side.