Artistic Rendering Project Beta Release

Artistic Rendering ProjectBeta Release Jeremy Shopf 11/21/06

Recap • Combine shape from shading with shading acquistion • Inspired by “Image-based Material Editing” • Get depth map from luminance • Apply arbitrary BRDFs to depth map • Awesome results

First Attempt • Get shape • Convert RGB to luminance • Use edge-preserving blur • Compress to simulate human visual system • Resulting values are used as depth • Calculate gradient • Get shading from shape • Assume isotropic surface shading • Estimate light direction in painting • Calculate angle of each pixel normal with light • For each pixel of a given angle, average all colors • Not good • Try and fit a function to it using least squares • Data too random to get anything remotely accurate

Source Image

First Attempt est kaput

Second Attempt • Find pixel with the greatest luminance • This must be the color the material exhibits when its normal is approximately the lighting direction • Find pixel with the lowest luminance • Weight by distance from pixel with greatest luminance • Define shading function as all pixels between the brightest and darkest pixels N dot L 0.0 1.0

Result.. N dot L 0.0 1.0

Improvements • What about when the artist chooses non-intuitive shading values • Pick greatest luminance as start, and closest pixel outside of object as end • Apply to painterly rendering!

Artistic Rendering Project Beta Release