This effect was generated in Filter Forge, a Photoshop plugin that allows you to create your own filters.
This filter mainly gives an image a cartoon style effect. (BTW, there are other similar filters in the library. This one uses ideas from Vladamir's Comic Book and photoman's Simple Sketch.)
Along with comic/cartoon art, it can also give an image strange looking tones (with the "line" controllers).
Tips:
1. It may be easier to start by checking "Just the Lines" to try to get an optimal "outline". (BTW, the Size, pixel parameter also controls line width).
2. Increasing the lightness or gamma helps contrast the colors with the black outline (and looks less photo-like).
3. To remove any unwanted black spots in an outline, render two images – one with Just the Lines, and one with just the colors (with Line Opacity at 0). Clean up the outline with white, paint in PS and re-blend that outline layer with "multiply" over the color layer.
comic cartoon outline pen ink pencil draw drawing line black white B&W
This filter has earned its author one of our rewards. They are given to the authors of popular filters and include a free copy of Filter Forge.