The human being is not able to handle all of the received information. The information obtained at the very first stages of human observation of the real world is always accompanied by, according to previous sentence, 'surplus' data. The area of image preprocessing serves as instrument for suppressing such undesirable features of image, which is sometimes equal to emphasizing the desired ones either by empirical or theoretical methods. Thereinafter we focus on describing some image preprocessing techniques. Very often an image contains much more information than can be perceived.
Details are invisible due to noise or other obstacles.
Some of image degradations are introduced by human factor. This includes improperly focused optical devices, construction defects etc. Our intention is to describe some of them and to try to eliminate their influence on the image. This can be achieved by using of explicit information about optical devices. While it is obvious that reconstructed image is merely an approximation of the original, the goal is to minimize the differences.