Digital Image Correction Research Articles

Authentication and correction of digital watermarking images

A novel function for image watermarking is introduced. The proposed function gives a restoration/correction capability to image watermarking as well as the detection and localisation of alterations. The basic idea of the proposed watermarking technique is to adopt conventional error control coding techniques for generating a watermark.

GERES: a prototype expert system for the geometric rectification of remotely-sensed images

Abstract GERES (GEometric Rectification Expert System) is a prototype expert system designed to assist in the process of geometric correction of digital remotely-sensed images. This paper contains a brief justification for its development, a description of its structure, and an overview of its operation.

Rectification of multichannel images in mass storage using image transposition

Rectification or geometric correction of digital images refers to the 2-dimensional resampling of an image data array onto a new grid which is distorted with respect to the original grid. When an image on a mass storage device is very much larger than the available computer central memory, it is important to choose an algorithm for rectification which minimizes data transfers (i.e., I/O time) between the mass storage device and central memory. Transposing image columns with rows allows simplification in resampling, which may then be done in two 1-dimensional operations, each along easily accessible image rows. The storage format of multichannel images, often interleaved channels-by-line, may introduce difficulties in transposition, however. A very efficient rectification algorithm is described that treats multiple channels as a third array dimension and uses a highly efficient, dimension-sorting algorithm for transposition.