dithering
Simulating more colors and shades in a palette. In a monochrome system that displays and prints only black and white, shades of grays can be simulated by creating varying patterns of black dots. This is how continuous-tone images are created in a monochrome printer (see halftone).In color systems, additional colors can be simulated by varying patterns of dots of existing colors. Dithering cannot produce the identical results as having the necessary pixel depth (levels of gray or colors), but it can make shaded drawings and photographs appear extremely realistic. See bit depth.
Dithering is also widely used to smooth curved and diagonal edges (see anti-aliasing).
 |
| Dithering a Color Image |
|---|
| An infinite palette of colors can be created by dithering. The right side is a magnification of the white box on the left. |
 |
| Text Is Also Dithered |
|---|
| At the very top of this example, the dithered word DATABASE is softer than the undithered word below it. The magnified view shows how lighter blue pixels fill in for the curves. When dithering is performed against edges, it is called "anti-aliasing." |
 |
| More Shades Than You Think |
|---|
| At a quick glance, this Android logo image appears to have only solid green, white and black colors. However, the magnified view of the robot's dithered ear shows several tints of those colors. See GIF. |
| (data, algorithm) | dithering - A technique used in quantisation processes
such as graphics and audio to reduce or remove the
correlation between noise and signal. Dithering is used in computer graphics to create additional colors and shades from an existing palette by interspersing pixels of different colours. On a monochrome display, areas of grey are created by varying the proportion of black and white pixels. In colour displays and printers, colours and textures are created by varying the proportions of existing colours. The different colours can either be distributed randomly or regularly. The higher the resolution of the display, the smoother the dithered colour will appear to the eye. Dithering doesn't reduce resolution. There are three types: regular dithering which uses a very regular predefined pattern; random dither where the pattern is a random noise; and pseudo random dither which uses a very large, very regular, predefined pattern. Dithering is used to create patterns for use as backgrounds, fills and shading, as well as for creating halftones for printing. When used for printing is it very sensitive to paper properties. Dithering can be combined with rasterising. It is not related to anti-aliasing. |
Want to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit the webmaster's page for free fun content.
| ?Page tools | ||
|---|---|---|
|