Patent ID: 7492484

Claim:
An image signal processing method of limiting the amount of toner adhesion, comprising: converting image data for each color plane into first amount-of-toner-adhesion data, the image data for each color plane being cyan (C), magenta (M), and yellow (Y); on the basis of a preset amount-of-toner-adhesion threshold value table, converting the first amount-of-toner-adhesion data for each color plane into second amount-of-toner-adhesion data with a limited amount of toner adhesion; the second amount-of-toner-adhesion data stick 2 (C), stick 2 (M), stick 2 (Y), and stick 2 (K) are calculated on the basis of the following equations: stick2 ( C )=stick1 ( C )−(|all-limit|×stick1 ( C )/all) stick2 ( M )=stick1 ( M )−(|all-limit|×stick1 ( M )/all) stick2 ( Y )=stick1 ( Y )−(|all-limit|×stick1 ( Y )/all) stick2 ( K )=stick1 ( K )−(|all-limit|×stick1 ( K )/all) where limit is the threshold value setting table value, all=stick1 ( C )+stick1 ( M )+stick1 ( Y )+stick1 ( K ) stick1 (*) is the amount-of-adhesion value before change, * indicating CMYK, and stick 2 [*] is the amount-of-adhesion value after change, * indicating CMYK; and converting the second amount-of-toner-adhesion data into an image signal.