A Novel Method For Compressing Images Using Discrete Directional Transforms
Gisle Bjøntegaard · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1988
The main purpose of this paper is to present a coding method based on a new class of transforms that will be named Directional Transforms (DT). The idea behind using DT is, that the picture content shall determine which one out of several - 16 used here - transforms will describe the picture most efficiently. Most of the other aspects of the coding method are well known from hybrid coding schemes 2,3 - like two dimensional block transform, prediction by blockwise motion compensation and variable length coding (VLC) of transform coeffisients. It is shown that the use of DT gives both saving of bits to describe the natural images and subjectively better looking pictures due to cleaner reconstructions of edges and lines.