Open a jpeg picture of person's head. Convert to grey and make the
document 'indexed'
Go to menu...
Effects > Greyscale (Gamma corrected)
Image > Convert to Indexed
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Reduce the number of colors to just 3 indexed colors. Go to menu...
Image > Convert to Indexed
Recommended options for best quality-->
Wu Quantize(Diameter based weighting)
dithered
![Image](http://i1176.photobucket.com/albums/x323/don570/screenshot-quantize_zpsd46197dc.png)
If you wish you can use black paintbrush to blacken the background
behind the head.
For more editing you must return image back to RGB i.e. 24 bit color
Image > Convert to RGB
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Tip : to continue to edit with a paint brush the go to menu...
Pallette > Load Default
You will now have access to more colors in your pallette.
You will be able to modify the image with any color imaginable!
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To reduce the dithered look a gaussian blur is needed.
For a Gaussian blur of 1 go to menu...
Effects > Gaussian Blur
![Image](http://i1176.photobucket.com/albums/x323/don570/screenshot-gaussian_zps3156a3cc.png)
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To give more contrast go to menu and adjust contrast and gamma
Effects > Transform Color...
Here is final image suitable for book cover
![Laughing :lol:](./images/smilies/icon_lol.gif)
![Image](http://i1176.photobucket.com/albums/x323/don570/screenshot-final-grey2_zps8226231e.png)
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