Spatial Resolution Conversion and Enhancement Using Nonincreasing  Operators

doi:10.1117/PM29.ch5

Spatial Resolution Conversion and Enhancement Using Nonincreasing Operators

Book: Enhancement and Restoration of Digital Documents: Statistical Design of Nonlinear Algorithms

Author(s): Robert P. Loce, Edward R. Dougherty

Published: 1997

https://doi.org/10.1117/PM29.ch5

Author Affiliations +

Abstract

Technologies that enable portability of document bit maps are of prime importance to digital document processing systems. For example, digital documents are often printed or displayed using different devices, where each device may operate at a different spatial sample resolution. It is desirable for the image to have an appearance that is consistent between all of these devices, or possibly enhanced on a chosen device. Methods for spatial resampling of binary images are at the root of document portability technology. Other fields of image processing often operate in the gray-scale setting, and resampling may be adequately performed by some spline-fitting technique. For binary digital documents these methods are typically not suitable. In this chapter we examine two methods for performing spatial resampling using nonincreasing operators that are more appropriate for the binary image setting.