| 摘要 |
A first converting circuit converts K-level image data, and suppresses a diffusion range of data by an N-level converting circuit. The N-level converting circuit converts a K-level image into an N-level gradation image (K>N). An image memory stores the N-level gradation image. An estimating circuit converts the N-level gradation image into an M-level gradation image (N<M). A second converting circuit returns the M-level gradation image into the form before the conversion according to a conversion amount from the first converting circuit. Accordingly, density ripple can be suppressed even in a small scanning aperture. A control circuit sets a conversion table to the first converting circuit and the second converting circuit according to a setting signal from a control panel, and outputs a control signal to the estimating circuit, so that processing mode is set in response to different images, and image quality is adjusted.
|
