| 摘要 |
<p>PROBLEM TO BE SOLVED: To generate a high order hierarchy images capable of restoring low order hierarchy images close to source images by computing the pixel value of a second image using through the use of the pixel value of a first image and a preliminary coefficient, comparing both pixel values, updating a prediction coefficient stored in a storage means corresponding to a compared result and updating the pixel value of the first image corresponding to the compared result. SOLUTION: A decoding circuit 4 uses the pixel value of an initial high order hierarchy image, inputted via a switch 3 and the prediction coefficient supplied from a prediction coefficient memory 5, computes the pixel value of the low order hierarchy image, and outputs it to an error-computing circuit 6. The error-computing circuit 6 computes the S/N ratio to the source image of the low order hierarchy image inputted from the decoding circuit 4 and outputs it to a convergence deciding circuit 7. The convergence deciding circuit 7 computes the increase amount of the S/N ratio inputted from the error computing circuit 6 and decides whether or not the increase amount is converged. When it is decided that the increase amount does not converge, the pixel value of the high order hierarchy image is updated to an appropriate value.</p> |
