About one method of low-speed filtration of sonar images

A low-speed filter of digital images which uses a new function for com-pression arraying is offered. The proposed filter's algorithm consists of two stag-es. On the first stage 5 × 5 window is moved on the image so that every pixel gets in the center of the window once and the 8 adjacent pixels' brightness levels are calculated. On the second stage the central pixel's brightness level is calculated using the new brightness levels of the 8 adjacent pixels. At the same time only the central pixel changes its brightness on the image. The comparison of the pro-posed filter with well-known Gaussian filter has been made by means of PSNR noise pollution criterion and brightness histogram. It is shown that ac-cording to the PSNR criterion the proposed filter virtually isn’t inferior to Gauss-ian filter: images processed with the proposed filter have a wider brightness level spectrum.