IPU
Image processing function overview
The image signals from the SBU are subjected to various image processing, and output to the
controller (memory). The image signals from the controller (memory) are received, and output to
the LDB (the LDB is provided in the write unit).
Image processing overview (copy application)
Digital signal data output from the SBU is subjected to shading correction and line interval
correction, as well as image processing, which are performed by the IPU. Finally, the data is sent to
the machine as digital signals-4 bit/pixels.
Image processing items Details
Shading correction
Corrects for uneven scanner lamp lighting, and scatter in CCD light
receiving sensitivity.
Line interval correction
Line shift during subscanning magnification/reduction by scanner.
Corrects integer part.
Dot correction
Line shift during subscanning magnification/reduction by scanner.
Corrects below decimal point.
Vertical line correction Corrects a vertical striped image during sheet-through ADF.
Image area separation Determines text parts and photo parts of image.
Scanner gamma
correction
Corrects scatter of image data relative to exposure amount.
From reflectivity linear to density linear.
Filter Performs image sharpness adjustment and removes moire.
ADS Performs natural complexion removal in full color mode.
Color compensation
preprocessing
Determines hue in masking mode, and improves chromaticity.
Color compensation Converts RGB data to density value CMYK data of color materials.
Image magnification
change
Arbitrarily changes main scanning magnification, subscanning fixed
image reduction and magnification of scanner image.
Image shift function Shifts image data in the main scanning or subscanning directions.
Image binarization
function
In scanner mode, outputs a binary signal.
7. Detailed Descriptions
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