Halftone Image From Greyscale Image Tutorial
I think this might be scriptable if anybody wants to try to do it.
1. Start off with a greyscale image. If you have a color image then do a [Color] [Desaturate] on it first. And then create another layer above it that is all black canvas area. And change the layer mode to Dodge.
![Image](http://www.gimpchat.com/files/1735_Horse1.png)
2. On the black dodge layer run the [Filter} [Render] [Patterns] [Grid] filter on it. In the grid dialog choose a width for Horizontal and verticle lines of 1 to 4 or so. Choose the spacing between the lines at perhaps 10 to 20. And make the color of the lines white, and click OK.
![Image](http://www.gimpchat.com/files/1735_Horse2.png)
Now Gausian blur the dodge layer to kind of round off the squares, followed by a [Color] [Auto] [Stretch Contrast] to force the colors to stretch from full black to full white.
![Image](http://www.gimpchat.com/files/1735_Horse3a.png)
![Image](http://www.gimpchat.com/files/1735_Horse3b.png)
4. Then do a [Layer] [New From Visible] and run the [Color] [Threshold] filter on it by moving the slider to the right.
![Image](http://www.gimpchat.com/files/1735_Horse4.png)
Since this is all being done manually it gives a lot of room for adjustment. You can try to invert one of the layers. You can also use a filter like [Distorts] [Curve Bend] or [iWarp]. Curves can also be used on the layers to make things thicker or thinner in the results. You can also try this with other settings inside of the [Grid] dialog box. You can use the [Grid] ddialog to create only verticle or only horizontal lines etc.
Pegleg