6 Click OK to apply the filter. Adding and removing noise In images, “noise” refers to randomly-colored pixels. Noise can be good or bad. For example, you can apply noise to computer-gener- ated graphics to make them appear more photographic. You can also use a filter that removes noise to minimize the appearance of tiny scratches or other artifacts present in the source material or intro- duced during digitizing. Noise commands work with all image modes except Black & White and Indexed. To add noise to selections 1 Select one or more paint objects to adjust. Select an area in one image to adjust the selected area only. 2 Choose Image > Filter > Noise > Add Noise. 3 Enter 1 to 999 for Amount to specify how far the color of the noise can vary from the original color. 4 Choose the Uniform or Gaussian distribution option: •   Choose Uniform to apply colors randomly picked within the Amount specified. Canvas evenly distributes the color of the noise across a range of colors. This option gives the smoothest effect. •   If you want the noise to favor lighter and darker colors within the specified range, choose the Gaussian option. This option creates a more pronounced effect than Uniform. 5 If you want to add noise of different brightness levels of the original color, select Monochromatic. 6 Click OK to apply the noise settings. Removing noise from selections You can remove noise from an image or selection using the Median, Despeckle, or Dust & Scratches filters. The Median filter removes noise by averaging the color of pixels. The Despeckle and Dust & Scratches filters remove noise by selectively blurring regions of the selection.
Canvas 8 Help: Image adjustment and correction (21 of 24)                                           Page #703