Graham filter

Graham Filter affects only smooth brightness changes leaving the sharpest edges unchanged. Normally, this command enhances the quality of an image background. The larger the filter size, the larger background details will be smoothed.

You can also select the color channel (R, G, or B buttons), total brightness (V button), hue (H button) or color saturation (S button) of the image to be filtered.

This filter is recommended to improve the quality of images that have been compressed using the JPEG standard.