The Noise menu allows to add or remove graininess in your image. It contains the effects: Add Noise, Dust & Scratches, Median.
Add Noise. The filter adds noise to an image.
In the Distribution section, choose a type of noise distribution: Uniform, Impulse, or Gaussian.
Color Noise check-box. If the check-box is enabled, the color noise will be added to an image. If the check-box is disabled, only the b&w noise will be added.
Amount (0-100). The parameter adjusts the overall amount of noise in an image.
Dust & Scratches. The filter reduces noise by blurring dissimilar pixels within the specified radius.
Radius (1-100). The parameter determines the size of the area, within which the dissimilar pixels will be blurred.
Threshold (0-100). The parameter determines how much the pixels must differ in order to get blurred.
Note: Apply this filter to a small selected area containing defects, as it can reduce not only noise but also image detail.
Median. The filter reduces noise in an image by averaging the color values of similar pixels within a predetermined radius.
Radius (1-100). The parameter sets the radius of the area within which the colors of individual pixels will be compared and averaged.
If the Fixed Preview Area check-box is enabled, all changes will be displayed in a small preview area. If the check-box is disabled, the changes will be applied to the area visible in the Image Window.
Click Default to restore the original settings.
Click OK to apply the changes and close the effect dialog box.
Click Cancel to close the dialog box without applying changes.