| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the memory capacity necessary for the image compression by carrying out the entropy coding of a frequency component that has undergone the specific frequency conversion to the image data. SOLUTION: The pixel data representing an image to be coded are inputted from an image input part 101 in the order of the raster scanning. The one- dimensional discrete wavelet transformation parts 102, 105 and 108 perform the horizontal discrete wavelet transformation. The buffers 103, 106 and 109 store temporarily the image data which are needed for the following stages. Meanwhile, the one-dimensional discrete wavelet transformation parts 104, 107 and 110 perform the vertical discrete wavelet transformation. An entropy coding part 112 performs the entropy coding and outputs the codes via a code output part 113. The data processing size of each of wavelet transformation parts 108-110 is halved against the data processing size of each of wavelet transformation parts 105-107. As a result, the capacity of the buffer 109 can be halved to the buffer 106.</p> |
