| 摘要 |
PURPOSE:To improve an encoding efficiency by using a block applying the correlation of the minimum value and a maximum value of a simple difference as a predictive block according to the simple difference. CONSTITUTION:A difference for a screen unit between an input screen block and a reproduced predictive screen block read from a frame memory 2 is calculated in a difference calculator 4 and fed to an accumulator 51 and a correlation calculator 52 for every prescribed block. In the accumulator 51, the absolute value of a difference value is taken for every picture element, the difference absolute value for every clock of the prescribed blocks is accumulated and fed to a controller 53. In the correlation calculator 52, the block of the difference value is formed to obtain the correlation value of the picture element in the respective blocks and feed to the controller 53. In the controller 53, when the minimum value of the accumulated difference absolute value is smaller than a prescribed threshold, the correlation supporting a maximum correlation value is strong and a control signal having the block including much low frequency component as a preliminary block is fed to a variable delay device 3. |
