Eastman-kodak Company

Mark R Knudson

David William Dellert

James I Hackett

Kevin C Scott

The apparatus and method of the present invention utilizes three scaling functions for bi-tonal digitized image data such as documents. The digitized document resolution (i.e. from a digitizing scanner) may be different from the resolution of an image output device (i.e. laser printer, CRT display, fax machine, etc.). The invention takes in the scanned image data and scales the data to compensate for the resolution mismatch of the output device. Although the invention is intended for document archive applications (such as scanning documents on microfilm), the scaling can be performed on any bi-tonal image.

Scaler gate array for scaling image data

Apparatus and accompanying method(s) for digitally scaling, particularly reducing, an original image to yield a scaled image particularly suited for display by a document workstation in an image management system as one image in a composite multi-image display. Reduction scaling is achieved by logically combining pixels values in each block of pixels in an original bi-tonal image, preferably through an 'OR' operation, in order to generate a corresponding single pixel value in a scaled bi-tonal image. To reduce the original image by a non-integer scale factor, the pixel blocks that form the original image are assigned differing groupsizes that periodically vary on a two-dimensional pattern from block to block throughout the original image. The average value of the periodic variation occurring in each direction throughout a sufficiently large two-dimensional area in the original image substantially equals the fractional portion of the non-integer scale factor. If integer scaling is desired in either the horizontal or vertical direction, then the groupsize remains the same along that direction from block to block throughout the original image. Alternatively, to digitally enlarge (magnify) an original bi-tonal image, each pixel in the original image is replicated to form a corresponding block of pixels in a destination (enlarged) image. In order to two-dimensionally magnify the source image by non-integer scale factors in both the horizontal and vertical directions, the groupsize of successive pixel blocks in the destination image is appropriately varied, also through a corresponding two-dimensional pattern. The groupsize remains fixed along either direction if the original image is to be magnified along that direction by an integer scale factor.

Growing community of inventors

Rochester, NY, United States of America

Mark R Knudson