the Woodcut Effect
menu:
Filter >
Artistic >
Woodcut...
You'll see a simple interface with a slider. Use it to change the appearance:
Once you have a desired effect or one that's close enough, you can further use it in several ways. In this example we combine it with the original. The Original was placed in the Swap buffer and merged with the image created through the woodcut filter.
That's it, in a nutshell. Of course you can explore many uses and variations of this filter, especially by combining its effects with others such as the other effects in the Artistic group, like Oilify, or the Graphic Pen with its many iterations, or the Brush strokes effect and wet paint.
You can quite easily use this to make something look like it was a print from a woodcut.
Here's an animation that shows the changing appearance of the same image when moving the slider.