Patent ID: 6997624
Filing Date: 2006-02-14
Classification: G06K,H04N

Abstract:
1. An image forming apparatus that receives image data and forms an image based on the image data, the image forming apparatus comprising: a dividing unit that divides the input image data into data groups based on a prescribed number of pixels in main scanning direction; a tone setting unit that sets tone for each data group created by the dividing unit based on the number of pixels having a prescribed value in the data group; wherein the tone setting unit sets the tone based on the ratio of the number of ON pixels to the total number of pixels in the data group; a position attribute setting unit that sets the position attribute for each data group created by the dividing unit based on arrangement of pixels having a prescribed value in the data group; and a pulse width modulation unit that performs pulse width modulation in response to a driving clock signal corresponding to a resolution of the input image data divided by the number of pixels in a data group created by the dividing unit, wherein the pulse width modulation unit performs exposure of each pixel for output image based on the pulse width in accordance with the tone set by the tone setting unit and the intra-group position in accordance with the position attribute set by the position attribute setting unit.