Halftone compression with sharpness preservation

Details Halftone compression with sharpness preservation Halftone compression with sharpness preservation

1990-03-29

1993-06-01

Evans, Arthur G.

395132, G06K 1500

Patent

active

052167534

ABSTRACT:
Method and apparatus for compressing and enhancing gray-level, halftone, image data in copiers and printers. The input data is digitally halftoned to provide input halftone cells containing a plurality of individual pixels. The pixel density distribution is examined to determine the relative position within the cell of the densest pixels. The gray-level density value for the entire cell is also ascertained. The distribution determines the particular threshold matrix which is used to convert the density value of the input cell into pixel density values which form an output halftone cell. The various matrices have distribution patterns which place the lower threshold values at the position in the output cell corresponding to the position of the densest pixels in the input cell. The cell density value and the matrix selection designator are stored in memory at different bit levels.

REFERENCES:
patent: 4246614 (1981-01-01), Knox
patent: 4786975 (1988-11-01), Postl
patent: 4974171 (1990-11-01), Yeh et al.

Affiliated with

Also associated with

Rating

Halftone compression with sharpness preservation does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Halftone compression with sharpness preservation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Halftone compression with sharpness preservation will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1821465