Download presentation

Presentation is loading. Please wait.

Published byNicole Townsley Modified about 1 year ago

1
Binary Shading using Geometry and Appearance Bert Buchholz Tamy Boubekeur Doug DeCarlo Marc Alexa Telecom ParisTech – CNRS Rutgers University TU Berlin Computer Graphics Forum Vol. 29, N. 6, 2010 Presented at Eurographics 2011

2
Binary Drawing Depicting scenes using 2 colors

3
Conversion Binary Rendering Lighting Reflectance Geometry Camera

4
Related Work Line Drawing [DeCarlo 2003][Judd 2007] Image Binarization [Mould and Kaplan 2008] Local shading operators [Vergne 2008] Half-Toning [Floyd and Steinberg 1976] [Ostromoukhov and Hersch 1995]

5
Analysis Variational Rendering Model Per-pixel decision Contradictory criteria Geometry enhancement Low shading depiction power

6
VARIATIONAL BINARY RENDERING

7
Variational Binary Shading Deferred shading framework Rendering data structured as a ST image graph Edges energies derived from geometry and appearance Final rendering as a min cut in the image graph

8
Deferred Shading Generate a set of arrays (render buffers) – Geometric Properties – Appearance Properties Rasterization Ray Tracing

9
Graph construction Standard Source-to-Sink Image Graph {V,E} Image Pixels Source (white) Sink (black) Image Connectivity Edges to Source Edges to SInk

10
Appearance Contribution to the Graph Through terminal weights on Appearance initiate B/W segmentation Experiments using : – Diffuse component – Specular component – Headlight component – Ambient Occlusion/Accessibility component Terminal Weights

11
Appearance Graph Terms Global to local feature control using spatial averages Support size Local term: Sign:locally lighter or darker Weighted combination to the global measure.

12
Global versus Local Thresholding GlobalLocal

13
Geometry Contribution to the Graph Modelled with neighbor edge weights Tailors anisotropic, non-local B/W diffusion Redistributes B/W values to enhance geometric features Based on: – View depth values – View dependent curvature, estimated as screen space normal derivatives [Judd 2007] Geodesic distance on the Gauss sphere Unit surface normal gathered at

14
Geometric Term Local curvature normalization: Support size Yields neighbor edge weights:

15
Geometry Contribution Modulation

16
Small components are successively connected

17
Graph Minimum Cut Max Flow Min Cut Theorem – Shortest split path in the graph →Feature size control through graph energy Separate the graph in two components Boykov and Kolmogorov implementation [2004]

18
Cut performance Rendering buffers can be speed up using rasterization Measured on a Core2Duo 1.83GHz (single thread)

19
RESULTS

20
Binary Shading Global to local features Appearance & geometry depiction Large variety of style Interactive control

21
Comparison to Line Drawing Line Drawing Binary Shading

22
Combination with Line Drawing

23
RGBN Picture Rendering [Toler-Franklin 2007]

24
Combination with Line Drawing

25
Comparison to Thresholding Diffuse Component Thresholding Over Gaussian Filtering Binary Rendering

26
Comparison to Thresholding

27
Comparison to Image Binarization (b,e) equivalent to [Mould and Kaplan 2008]

28
INTERACTIVE CONTROL On-going work

29
Interactive Control Solution 1: slider-based, for experts – Accurate control – « Too much » control for novice users Solution 2: painting interface

30
Paint Interface Supervised sparse B/W contraints Derive the graph energy structure

31
Paint Interface

32
LIMITATIONS AND FUTURE WORK

33
Animation … most of straightforward solutions have some temporal coherency failure cases. Works most of the time but…

34
K-color Rendering Extend to multi-label cuts Alternative energy minimizer – Lloyd relaxation/k-means – Mean Shift k-Component cut Vector Rendering

35
CONCLUSION

36
Binary Shading as a Single Cut Global solution Local to global control Appearance vs geometry control High level control For automatic binary drawing from 3D Scenes, decals, cut-out, etc…

37
Thank you Binary Shading Using Geometry and Appearance. Bert Buchholz, Tamy Boubekeur, Doug DeCarlo and Marc Alexa Computer Graphics Forum Vol. 29, Nb. 6, 2010 Presented at Eurographics 2011

Similar presentations

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google