Dither
Dithering is the intentional use of noise (random sounds) to reduce the error of compression.
Example below:
Figure 1. Original photo; note the smoothness in the detail.
Figure 2. Original image using the web-safe color palette with no dithering applied. Note the large flat areas and loss of detail.
Figure 3. Original image using the web-safe color palette with Floyd–Steinberg dithering. Note that even though the same palette is used, the application of dithering gives a better representation of the original.
Figure 4. Here, the original has been reduced to a 256-color optimized palette with Floyd–Steinberg dithering applied. The use of an optimized palette, rather than a fixed palette, allows the result to better represent the colors in the original image.
Figure 5. Depth is reduced to a 16-color optimized palette in this image, with no dithering. Colors appear muted, and color banding is pronounced.
Figure 6. This image also uses the 16-color optimized palette, but the use of dithering helps to reduce banding.
Dither Media
Reducing amplitude resolution plot
An illustration of dithering. Red and blue are the only colors used but, as the red and blue squares are made smaller, the patch appears magenta.
256 color dithering with IrfanView
Color dithering on a towel
A smooth gradient using ordered dithering from black to white, using only three colors (black, gray and white)
This image is part of a series of images on dithering algorithms. The whole series, as well as documentary information can be viewed at User:Gerbrant/Dithering algorithms.
This image is part of a series of images on dithering algorithms. The whole series, as well as documentary information can be viewed at User:Gerbrant/Dithering algorithms.
This image is part of a series of images on dithering algorithms. The whole series, as well as documentary information can be viewed at User:Gerbrant/Dithering algorithms.
This image is part of a series of images on dithering algorithms. The whole series, as well as documentary information can be viewed at User:Gerbrant/Dithering algorithms.
