IMAGE COMPANDER AND PIXEL NUMBER INCREASING DEVICE

摘要

PROBLEM TO BE SOLVED: To enhance image quality of a magnified image with respect to an image compander that reproduces the magnifies image, corresponding to an original image from a reduced image. SOLUTION: Original image data consist of values Pyx of about 1,000×600 pixels. A 1st matrix M1 consisting of values Pyx of 64×64 pixels is extracted from the original image data. A 2nd matrix M2 is generated, whose pixel value is a mean value of values Pyx of 8×8 pixels configuring each block B1, that is the each component of the 1st matrix M1 constituting the original image data. Two-dimensional discrete cosine transformation is applied to the pixel values of the 2nd matrix M2 to obtain a matrix MD consisting of 8×8 DCT coefficients. Extended two-dimensional inverse discrete cosine transform is applied to the matrix MD, to obtain a 3rd matrix M3 consisting of values of 64×64 pixels. Extended image data consisting of the 3rd matrices M3 are converted into the same coordinate system as that of the original image data, and the result is stored in a recording medium.