Patent ID: 6643397
Filing Date: 2003-11-04
Classification: H04N

Abstract:
An image data processing apparatus comprising;determining means for determining whether input image data supplied is a color image mode or monochrome image mode; histogram forming means for forming a histogram indicating the frequency of occurrence of density levels for each of a plurality of color component signals, corresponding to the input image data; reference value calculating means for calculating a first reference value for density adjustment for the color image mode, corresponding to the histogram formed by the histogram forming means; reference value converting means for converting the first reference value for the color image mode into a second reference value for the monochrome image mode and outputting the second reference value; and density adjusting means for adjusting the density of the input image data by using the first reference value when the determining means determines that the input image data is the color image mode and using the second reference value output from the reference value converting means when the determining means determines that the input image data is the monochrome image mode and then outputting output image data.