Two methods of image extension

Abstract Most operations in image processing involve application of a mask centered at each pixel in an image. Consequently, in order to preserve image size under various operations, it is necessary to extend an image outside its borders for the number of columns and rows equal to half the mask size. This paper describes two methods of image extension so that image size may be preserved under various image processing operations. An algorithm is provided for each method and the results obtained are compared in terms of their statistical properties and aesthetic value.