Patent ID: 8035870

Claim:
An image forming apparatus comprising: a first sensor configured to convert reflective light from an original to a red signal, a green signal and a blue signal; a second sensor configured to convert the reflective light from the original to a monochromatic signal; a selector configured to select a color signal which is one of the red signal, the green signal and the blue signal; an image signal processor configured to generate two signals from the monochromatic signal and the color signal without using the other two of the red signal, the green signal and the blue signal than the color signal; and a printer configured to print an image based on the two signals, wherein the image signal processor includes: a first converter configured to perform conversion to enhance color extraction precision of the color signal selected by the selector; a second converter configured to perform conversion to give priority to tone characteristics for the monochromatic signal produced due to the conversion by the second sensor; and a density converter configured to perform density conversion for the monochromatic signal converted by the second converter, in accordance with a signal level of the color signal converted by the first converter.