SKETCHING BY PERCEPTUAL GROUPING

Sketch is used for rendering the visual world since prehistoric times, and has become ubiquitous nowadays with the increas-ing availability of touchscreens on portable devices. How-ever, how to automatically map images to sketches, a prob-lem that has profound implications on applications such as sketch-based image retrieval, still remains open. In this pa-per, we propose a novel method that draws a sketch automat-ically from a single natural image. Sketch extraction is posed within an unified contour grouping framework, where percep-tual grouping is first used to form contour segment group-s, followed by a group-based contour simplification method that generate the final sketches. In our experiment, for the first time we pose sketch evaluation as a sketch-based object recognition problem and the results validate the effectiveness of our system over the state-of-the-arts alternatives