Computer Graphics & Visual Computing (CGVC) 2020

Continuous-Line-Based Halftoning with Pinwheel Tiles

Abdalla G. M. Ahmed

Various kinds of animations enabled by our continuous-line drawing framework. The example in the top is suitable for transition effects in presentations, the one in the middle suits animated GIFs, while the morphing one in the bottom demonstrates that we can even cope with arbitrary motion pictures.

Abstract

We describe a technique for continuous-line-based halftoning with space-filling curves, namely Segerman's pinwheel curve, which is based on Conway's pinwheel tiles. We adapt the length of the curve passing through the tiles in accordance with a supplied density map, e.g. a grayscale image. We use the subdivision depth of the tiling for a coarse control of the curve length, and we describe a finer control to faithfully match the density map. Our technique exhibits excellent temporal coherence, making it suitable for animated images.

Demos

This animation is obtained by passing an animated image as and input.

In the video on the left, we animate the line weight parameter. On the right-hand video we morph between two input images.

Downloads

	Paper PDF (166 KB)
	Source Code ZIP (10 KB)

Bibtex

@inproceedings {vc.20201149,
    booktitle = {Computer Graphics and Visual Computing (CGVC)},
    editor = {Ritsos, Panagiotis D. and Xu, Kai},
    title = {{Continuous-Line-Based Halftoning with Pinwheel Tiles}},
    author = {Ahmed, Abdalla G. M.},
    year = {2020},
    publisher = {The Eurographics Association},
    ISBN = {978-3-03868-122-9},
    DOI = {10.2312/cgvc.20201149}
}