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Most quantizer algorithms reduce the number of colors in an image, but the colors appear as dots throughout the image. When quantizing images which we know have a fixed number of colors, say, logos, it is desirable that similarly colored pixels are clustered together. Is there a quantizing algorithm that is suitable for this purpose?
Posted 23-Mar-10 3:14am
Shree1.6K

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## Solution 1

many quantization functions will allow you to control the amount of dithering that occurs once the output palette has been determined. dithering is what gives you the 'dots' - it's an attempt to blend two colors in order to better represent to original image.

if you can turn off dithering, you'll get nice clean edges between areas of solid color.
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## Solution 2

Threshold is the obvious dithering technique (or "quantization algorithm") that makes similar sections appear as a solid. If you want to perform a statistical analysis to decided which colors to use beforehand, you could then adjust each pixel according to which of those chosen colors it is closest to. This would give a cartoon look (i.e., looks like cell shading rather than interspersed dots), which I believe is what you are after. Not sure if there is a name for the algorithm which combines closest match and statistical analysis, but if not then just create it and give it any name you like (e.g., Smart Threshold). :)
Hiren Solanki 1-Sep-10 1:51am

intresting

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