Structure Grid for Directional Stippling

Minjung Son
POSTECH

Yunjin Lee
Ajou University

Henry Kang
UMSL

Seungyong Lee
POSTECH

Graphical Models, vol 73, no 3, May 2011

(a) Original Image

(b) Kim et al. 2008

(c) Our Result

Abstract

This paper presents a novel method to convert a photograph into a stipple illustration. Our method addresses directional stippling, where the collective flows of dots are directed parallel and/or orthogonal to the local feature orientations. To facilitate regular and directional spacing of dots, we introduce the notion of a structure grid, which is extracted from the smoothed feature orientation field. We represent a structure grid as a 2D texture and develop an efficient construction algorithm that outperforms conventional Lloyd's method in terms of the rigor of dot alignment. Moreover, the criss-crossing nature of a structure grid allows for the inclusion of line primitives, providing effective description of dark tone. Given a structure grid, we determine the appropriate positions and attributes of primitives in the final illustration via rapid pixel-based primitive rendering. Experimental results show that our directional stippling method nicely reproduces features and tones of various input images.

BibTex

@article{Son-2011-structure-grid,
author = {Minjung Son and Yunjin Lee and Henry Kang and Seungyong Lee},
title = {Structure Grid for Directional Stippling},
journal = {Graphical Models},
year = {2011},
volume = {73},
number = {3},
pages = {74-87},
}