| 摘要 |
PURPOSE:To improve the efficiency of encoding by providing a parameter calcu lation part which supplies a weighting pattern corresponding to a current block to a weighting process part or forcibly sets the value of input image data on the side of a high frequency component to '0'. CONSTITUTION:Longitudinal and lateral position determination parts 3 and 4 detect the current longitudinal and lateral positions (x) and (y) of respective blocks from a horizontal and a vertical synchronizing signal, a clock signal, etc., by using a counter, etc. Then a parameter calculation part 5 selects the weighting pattern at the weighting process part 2 as preprocessing for quantization or encoding by using parameters which are given by an operator and indicate which position on a screen is increased in picture quality and the frequency components after orthogonal conversion by an orthogonal conversion part 1 are weighted. In another way, the values of more low frequency components of the input image data are set to '0' toward the peripheral part except in a high-picture-quality area. |
