| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a data compression device/method which can effectively decrease the mosquito noises or the like, without deteriorating unnecessarily the data compressibility. SOLUTION: The blocked image data are inputted to a DCT (discrete cosine transform) part 1 to undergo the DCT, quantized by a quantizer 2 and encoded by an encoder 3. The quantizer 2 quantizes the image data based on a quantization table 10 which is stored in a semiconductor memory, or the like. A least significant bit processing part 11 which is placed between the quantizer 2 and the encoder 3 performs the control to change the threshold that carries or borrows the places less than a decimal point to the least significant bit of the quantization data based on the table 10. Thus, a quantization error is substantially suppressed with no increase of the information content.</p> |
