envyLight: An interface for editing Natural Illumination Valentin JANIAUT Author: Fabio Pellacini (Darmouth College)

2 Natural Illumination ● Capturing the illumination from the real world. We store the environment light into a environment map (envmap).

3 Example of the Uffizi Gallery

4 Goal of envyLight ● Editing easily the light environment. ● Replace the current usage of Photoshop.

5 Interface ● From [KERR09], 3 groups of lighting interfaces: Direct edition of the light parameters. Direct interface Edit lighting features in the rendered image. Indirect interface Paint a goal image, light parameters are optimized to match this image. Painting interface

6 Select-and-modify workflow Select lighting feature. Select the envmap region. Edit lighting feature. Modify the envmap region

7 Lighting feature ● Highlight ● Shadow ● Diffuse gradient

8 Selection Algorithm X in X out

9 Create two new envmap Foreground envmap Background envmap

10 Result

11 Edit operation ● Brightness and Tint ● Contrast ● Translation ● Blur ● Sharpen

12 Brightness and Tint

13 Overview of the algorithm Select the lighting feature. Using Xin and Xout strokes. Separate the envmap in two envmap. The foreground envmap will contain the select lighting features. Edit the foreground envmap. Apply any transformation on this map. Then merge with the background.

14 Implementation Performance ● rendering: 0.2 s ● selection: 0.3 s ● edits: < 0.1 s

15 References ● envyLight: An Interface for Editing Natural Illumination. ● lication.php?id=envylight10 lication.php?id=envylight10 ● EnvMap gallery: ● HDR Capture of the sky: [STUMPFEL04]