Linear discrete image transforms

Image processing and analysis based on continuous or discrete image transforms is a classic processing technique. Image transforms are widely used in image filtering, image data compression, image description, etc.; they were actively studied at the end of the Sixties and in the beginning of the Seventies. This research was highly motivated by space flight achievements; first, an efficient method of image data transmission was needed, and second, transmitted images were often received locally or globally corrupted. Both analogue and discrete methods were investigated — analogue optical methods suffered from a lack of suitable high-resolution storage material, and the rapid development of digital computer technology slowed analogue research in the middle of the Seventies. However, much research is now being devoted to optical methods again, especially with new technological achievements in developing high-resolution optical storage materials. The main focus is in possible real-time image processing.