Line-growing cell tessellation for generating paper-mosaic images

Non-photorealistic rendering (NPR) techniques have been proposed for generating papermosaic images composed of regularly-formed paper-pieces such as ellipses or squares. Hand-made papermosaics, however, consist of various form of pieces. We present, in this letter, an NPR method for generating such paper-mosaic images composed of paper-pieces of various forms and visual effects by growing lines from points placed with the Poisson disk sampling (PDS) for tessellating an image into cells. Points are placed almost equidistantly by a radius-ordering PDS. The radius is shrunk around edges for preserving object boundaries. Images are tessellated by growing lines along contours of the luminance of each pixel. Extended examples are also shown with addition of gradation or hatching to every colored cell.