Digital scan converter and method therefor
First Claim
1. A digital scan converter, comprising:
- source means for supplying a continuously updated plurality of digital image values which define an image of a scanned object, each one of said image values indicating a value of said image at a respective one of a plurality of spaced image pixels distributed over predefined locations of a first coordinate system;
initialization means for preselecting, for each one of a plurality of spaced image pixels distributed over a second coordinate system, a respective group of image pixels from said first coordinate system which flank it, and for predefining a conversion relationship which enables the calculation of each one of said image pixels of said second coordinate system based on the image values of its said respective group of image pixels; and
conversion means, responsive to said source means and said initialization means, for calculating respectively and in real time, the image values of said plurality of image pixels of said second coordinate system to produce an image of said scanned object in a format required for said second coordinate system.
1 Assignment
0 Petitions
Accused Products
Abstract
A digital scan converter with an initialization circuit. The initialization circuit, for example, a dedicated circuit or a computer, relates each pixel in a converted image to two or more respective pixels which lie adjacent to it and which are selected from an original image which is generated by a scanner. The initialization circuit also calculates and makes available interpolation constants to be used in deriving the value of a given pixel in terms of its respective, adjacently lying, group of pixels. When the converted image has a raster scan format, a satisfactory image is obtained when the respective group of pixels consists of two pixels between which lies the pixel whose value is to be calculated. By predefining the relationship between the pixels in the converted and original images before actual conversion begins real time operation is achieved.
39 Citations
27 Claims
-
1. A digital scan converter, comprising:
-
source means for supplying a continuously updated plurality of digital image values which define an image of a scanned object, each one of said image values indicating a value of said image at a respective one of a plurality of spaced image pixels distributed over predefined locations of a first coordinate system; initialization means for preselecting, for each one of a plurality of spaced image pixels distributed over a second coordinate system, a respective group of image pixels from said first coordinate system which flank it, and for predefining a conversion relationship which enables the calculation of each one of said image pixels of said second coordinate system based on the image values of its said respective group of image pixels; and conversion means, responsive to said source means and said initialization means, for calculating respectively and in real time, the image values of said plurality of image pixels of said second coordinate system to produce an image of said scanned object in a format required for said second coordinate system. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
-
-
25. A digital scan conversion method for converting a first group of image pixel values associated with a first scanning format to a second group of image pixel values associated with a second scanning format, said second scanning format having scan lines which extend generally perpendicularly to scan lines associated with said first scanning format, said method comprising the steps of:
-
(a) preselecting for each image pixel of said second format a respective pair of image pixels of said first format which flank it generally along a scan line of said second format, each second format image pixel having its respective pair preselected prior to the beginning of a scan conversion process; (b) predefining, prior to the beginning of said scan conversion process and for each second format image pixel, a conversion relationship which produces a respective image value for said second format image pixel by applying said conversion relationship to said respective pairs of image pixels to produce said second format image pixel; (c) receiving a first stream of said first format image pixel values, said stream having an image pixel order in accordance with said first scanning format; (d) arranging said stream of image pixels as said respective pairs of image pixels and storing said pairs in a memory; (e) retrieving said pairs from said memory in accordance with an order which corresponds generally to said second scanning format; and (f) applying said conversion relationship to each said respective pair of image values, to produce a stream of converted image pixel values which are generally ordered in accordance with said second scanning format, said converted image pixels being produced at a rate which is not exceeded by a rate at which said converted image pixels are applied to a video processor of a raster scan device. - View Dependent Claims (26, 27)
-
Specification