| 摘要 |
<p>PURPOSE:To optimize image quality by utilizing the principle that two consecutive images or over in an animation image have large correlation in general and estimating an image code multi-value processing generated in each block with a code quantity, a quantization step and the distribution of a just preceding image so as to make generated code quantity for each area in matching with each other. CONSTITUTION:A subtractor 19 takes a difference between a frame already coded and a current frame to provide an output to a quantization section 4 and adds an absolute sum of difference signals of each area and provides an output of the sum to a step changeover section 34 as a correlation signal. A code quantity measurement device 20 measures a code quantity (y) for each area of a frame generated from a VCL section 5 implementing variable length coding and provides the output of the result to an object quantity calculation device 21 and a characteristic calculation device 22. The calculation device 21 accumulates the code quantity (y) of each area measured by the measurement device 20 and accumulates real code quantity generated actually from the start of coding till the current state. Furthermore, the total code quantity capable of being be sent is calculated by the total time from the start of coding up to now and the transmission speed per unit time.</p> |
