The Methods of Group Processing of Digital Images for the Reference Images Preparation

• Дата: 2020
• Автори: Юзефович , В.В., Цибульська , Є.О.
• Формат: Стаття
• Мова: Ukrainian
• Опубліковано: Інститут проблем реєстрації інформації НАН України 2020
• Теми: зашумлення зображень; метод медіанної фільтрації; еталонне зображення; навігація та наведення літальних апаратів; noising images; median filtering method; reference image; AV navigation and guidance
• Онлайн доступ: http://drsp.ipri.kiev.ua/article/view/225916
• Назва журналу: Data Recording, Storage & Processing

The methods of the joint processing of image series used to reduce some kinds of noise are considered. It is determined that for different types of image distortion appropriate to use different methods. The method with the average of brightness values allows to reproduce covered objects, makes temporary objects less contrasting, but it weakly affects the «white» noise. In contrast, the median filtering method significantly reduces «white» noise («graininess» of resulting image), but shaded or covered objects are generally not reproduced. The modified median filtering method is proposed. The expressions for pixels brightness, weight and normalization factors are determined. This method reduces Gaussian white noise on resulting image (as standard median filtering method), and also it permits to restore shaded or covered objects. The disadvantage of this method is the reduction of the brightness range of resulting image, so it requires an additional operation of «stretching» its range to [0–255]. There is proposed to prepare a reference image based on the joint processing of a series of selective images obtained from images of one area under different conditions. The result is a more "universal" reference image, which contains stable information features inherent in all images of the series. This approach will be enable to use the prepared reference image to solve the problem of an aerial vehicle navigation and guidance under different lighting conditions, at different times or seasons, etc. Tabl.: 3. Fig.: 9. Refs: 9 titles.