| 摘要 |
<p>PROBLEM TO BE SOLVED: To establish a technique for an image to be compressed and reproduced with fidelity higher than that of the original image, by using Wavelet transform as principle, which is considered to be more advantageous than the principles of Fourier transform and other discrete cosine transforms for JPEG as ISO Standards, concerning a digital image compression and reproduction technique, and to research into nuclears of various disclosed Wavelet transforms for creating the optimum transform nuclear for the image compression and reproduction. SOLUTION: A cross-spectrum analysis is performed between an original image before compression and an reproduced image after compression and reproduction, and a prescribed low-pass filter is configured as a target frequency characteristic in the low-frequency range, within which the main components of the image exist. So that a square error of the difference between the characteristic and the cross spectrum characteristics becomes minimum, reflecting the difference, Wavelet transform nuclear is utilized. Evaluation of this technique is performed on the cross-spectrum analysis, with a delay between the original image and the reproduced image, after compression and reproduction, being detected and taken into account.</p> |
