IMAGE SIGNAL PROCESSING APPARATUS AND IMAGE SIGNAL PROCESSING METHOD

摘要

A first adder circuit (101) adds an input image signal of a pixel of interest to each of values obtained by multiplying display errors of three pixels in a line immediately preceding the line of the pixel of interest by a weighting factor. Gradation candidate converting means (102) converts the gradation of the image signal as added into a plurality of usable gradations that may be used when adding the error of a left-hand adjacent pixel. A delay circuit (103) delays the image signal as added. A second adder circuit (104) adds the image signal as delayed to the value obtained by multiplying the error that has occurred at the left-hand adjacent pixel by the weighting factor. Gradation selecting means (105) selects, from among the plurality of gradation candidates, one that is the closest to the gradation of the image signal to which the error has been added, and outputs the selected one as the image signal of the pixel of interest. A difference circuit (106) calculates the display error of the pixel of interest.