Animating Streamlines with Orthogonal Advancing Waves

Constant speed    Variable speed

(a)                                                                                          (b)

Teaser: Two RAPSA images generated in (a) constant-speed mode and (b) variable-speed mode, respectively, for visualizing a 770 x 386 flow field. Smooth evenly-spaced hue differing, combined with adaptive luminance interleaving, accentuates individual flow streaks in HSL space to yield high inter-streamline contrast in the two RAPSA images yet without introducing artifacts. The perception of these tangential flow patterns is augmented by the orthogonal cascading waves built through synchronized luminance transition. The length of RAPs, constant in (a) but variable in (b), encodes the velocity magnitude.

Abstract

Self-animating image of flow through Repeated Asymmetric Patterns (RAPs) is an innovative approach for creating illusory motion using a single image. In this paper, we present a smooth cyclic variable-speed RAP animation model that emulates orthogonal advancing waves from a geometry-based flow representation. It enables dense accurate visualization of complex real world flows using animated streamlines of an elegant placement coupled with visually appealing orthogonal advancing waves. The animation model first performs velocity (magnitude) integral luminance transition on individual streamlines. Then, an inter-streamline synchronization in luminance varying along the tangential direction is imposed. Next, tangential flow streaks are constructed using evenly-spaced hue differing in the orthogonal direction. In addition, an energy-decreasing strategy is proposed that adopts an iterative yet efficient procedure for determining the luminance phase and hue of each streamline in HSL color space. To increase the contrast between flow streaks, an adaptive luminance interleaving in the direction perpendicular to the flow is further applied. We demonstrate the effectiveness of the animation model using some synthetic and real flows.

Paper


paper

Complex flow


16 critical points, x-axis symmetric       16 critical points, y-axis symmetric       16 critical points, center-based symmetric

24 critical points, x-axis symmetric       24 critical points, y-axis symmetric       24 critical points, center-based symmetric

Wind flow
 Wind flow

Northeast Pacific Ocean 

 Single Hue     Diff Hue

Hurricane Isabel

 Hurricane Isabel

3D Torus

Flow400_08_z      Flow400_00_x       Flow400_08_z

Paper proposed


Flow400_04_x        Flow400_18_y        Flow400_13_z

BibTeX