Ricoh B234 - Image Processing Flow

IMAGE PROCESSING
B234/B235/B236/D101/D102/D103 6-46 SM
6.9.3 IMAGE PROCESSING FLOW
Image processing is done by the IPU (Image Processing Unit), following the steps
shown below.
Overall image processing for this machine is designed to:
• Target edges with filters to improve the angles of text characters and reduce the
occurrence of moiré filled areas.
• Improve the evenness of granular areas in images
Shading Correction
Corrects the dispersion of the scanning lens
and CCD.
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Gamma Correction Background erase
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Pre-Filter Reduces the occurrence of moiré.
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Main Scan Magnification
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Auto Select
Determines if an image is text or raster
image data and processes the data
accordingly.
Selects the best methods for Filtering,
Density Control, and Grayscale Processing.
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Filtering
MTF and smoothing (MTF filter of previous
machines)
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Either of two filters is selected by Auto
Select above.
Independent Dot Erase Removes isolated pixels.
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Line Width Correction
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Density Control
Employs one of two gamma tables,
selected by Auto Select above
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Grayscale Processing
Error diffusion, dithering, or binary picture
processing
Black-and-white digitization or dithering is
selected by “Auto Select above.
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Video Path
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Application (printer)
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LD Unit