| 摘要 |
PURPOSE:To attain efficient data compression in which deterioration in picture quality is suppressed, by dividing a two-dimensionally arranged data block into prescribed shaped unit blocks, and setting the number of encoding bits independently at every block. CONSTITUTION:A picture data inputted from the outside is written in double buffers 10a and 10b alternately by every unit block arranged two-dimensionally consisting of picture elements of 16X16, and hereafter, an encoding processing is applied on every block. Data read out from the double buffer 10, after being cosine-transformed, are stored alternately in double buffers 12a and 12b, and weighing processing are applied on them at a weighing instrument 14. Weighed data are inputted to an integer instrument 15 at the next stage, and after the decimal point parts of them are deleted, they are added on a re-quantizer 16. And in the re-quantizer 16, quantization by different steps is performed again on every small blocks. |
