| 摘要 |
<p>An image contracting circuit (1) contracts a supplied original image. An upper-level image memory (2) holds an inputted upper-level image. A prediction tap extracting circuit (3) extracts a prediction tap from the upper-level image stored in the upper-level image memory (2) and outputs it to a mapping circuit (4), prediction coefficient creating circuit (5), and pixel value updating circuit (8). The mapping circuit (4) outputs a predicted image formed by performing calculation of a linear combination of the prediction tap and the prediction coefficient to an error calculating circuit (6). The error calculating circuit (6) calculates the difference (S/N ratio) between the pixel value of the predicted image and the corresponding pixel value of the original image. A comparing/judging circuit (7) controls a nonlinear processing circuit (9) according to the difference. The nonlinear processing circuit (9) adds a predetermined value to the pixel value of the pixel of the updated upper-level image or subtracts a predetermined value from the pixel value depending on the variation of the pixel value updated by a pixel value updating circuit (8).</p> |
