PhotoSketcher is an application that can turn your photos into something similar to pencil sketches. To process an image, you can simply drag and drop it onto the application window and PhotoSketcher will take care of the rest. All the effects are applied automatically, but you can change settings after an image has been processed to adjust it. The settings pane is located on the right, and from there you can change options like pen size and color, moisture, background style and color, brightness and contrast. There is a "colorize" option available, which takes some of the colors found in the original photo and applies them to the sketch for more interesting results.
There is a toolbar at the top, that lets you zoom your image in and out, rotate it and change the view mode. There are three modes available: Original, Sketch and Split. The first one shows the source photo only, the second one will display the sketch and the last one, a mixture of the both. On the left, you will see the original photo, and on the right the sketch.
PhotoSketcher can achieve great results with pictures that are even not the best in terms of quality. For the best results, you would need to use a picture with a blank background and an up close shot of a face. But this great app even was able to create great sketches from regular photos.
The latest version of PhotoSketcher, 1.6, adds support for Flickr uploads and 64-bit support.