Fast bitonal to gray scale image scaling

Details Fast bitonal to gray scale image scaling Fast bitonal to gray scale image scaling

1987-03-02

1989-05-09

Boudreau, Leo H.

Image analysis

Histogram processing

For setting a threshold

340728, 340731, 364723, 382 50, G06K 942

Patent

active

048295876

ABSTRACT:
A device for re-scaling an image to change the resolution with which discrete pixel values represent it includes a scan-line interface (40) and an alignment circuit (45) that assemble sets of the original pixel values into submatrices and apply them to a convolution engine (46), which computes new pixel values from them. X and Y scaling engines (58 and 60) control the re-scaling without having to generate original-pixel address at the rate at which new pixels are generated. The X scaling engine (58) simply indicates whether an output the currently supplied input data should be used to generate an output intensity value and, if so, whether it should be retained for generation of the subsequent intensity value, too. Similarly, the Y scaling engine (60) indicates whether the next scan line to be received should be used for generation of a scan line of output intensity values and, if so, whether it should be retained for generation of a subsequent scan line of output intensity values. In generating the new pixel values, the convolution engine (46) converts from the binary, black-and-white levels of the original pixels to gray-scale values for the new pixels to reduce the jaggedness that scale changes can cause.

REFERENCES:
patent: 4528693 (1985-07-01), Pearson et al.
patent: 4532602 (1985-07-01), Du Vall
patent: 4602346 (1986-07-01), Kawakami et al.
patent: 4603348 (1986-07-01), Yamada et al.
patent: 4725892 (1988-02-01), Suzuki et al.
"Principles of Interactive Computer Graphics" 2d. Ed., Newman and Sproull, McGraw-Hill Book Co., 1979.
"Fundamentals of Interactive Computer Graphics", Foley and VanDam, Addison-Wesley Publishing Co., 1982.
"High-Speed Image Scaling for Integrated Document Management", K. Tabata, 1984 ACM 0-89791-140-7/84/006/0036.
"The Display of Characters Using Gray Level Sample Arrays", J. Warnock, 190 ACM 0-89791-021-4/80/0700-0302.
"Scaling Binary Images with the Telescoping Template", Ulichney and Troxel, 1982, IEEE 0162-8828/82/0500-0331.
"Low Resolution Multi-Level Representation of Bilevel Images", J. Sara, S. B., MIT, 1980.
"Filtering High Quality Text for Display on Raster Scan Devices", Kajiya & Ullner, 1981 ACM 0-8971-045-1/81-0800-0007.
"Incremental Linear Interpolation", Field, 1985 ACM 0730-0301/85/0100-0001.

Affiliated with

Also associated with

Rating

Fast bitonal to gray scale image scaling does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Fast bitonal to gray scale image scaling, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fast bitonal to gray scale image scaling will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-95547