Patent ID: 7196819

Claim:
An image data conversion apparatus for converting input image data of four colors consisting of cyan, magenta, yellow and black into output image data, said image data conversion apparatus comprising: a detection section for detecting an existence of a point or an area on an image in which any one of cyan, magenta and yellow has a value exceeding a first predetermined value, and black has a value exceeding a second predetermined value, in accordance with the input image data; and a conversion section having two modes of a first mode wherein said input image data is converted into output image data which is independent of an existence of said detection section, and a second mode wherein in the event that the detection section detects an existence of the point or the area, the input image data is converted into an output image data which is representative of an existence of the point or the area; wherein when said detection section detects non-existence of the point or the area, said conversion section converts, in the second mode, the input image data into the same output image data as a case where the input image data is converted into the output image data in the first mode.