Baking And Compression For Dynamic Lighting Data

Sammanfattning: This report describes the development and prototype implementation of a method for baking and compression of lightmaps, in an environment with dynamic lights. The method described can achieve more than 95 % compression eciency, and can be easily tuned with only two parameters. Even without specic tuning, the prototype consistently achieves signalto- noise ratios above 30 dB, reaching 60 dB in some scenes. Compression is achieved in four steps, rst by using image segmentation and function approximation to reduce the data-size and then using a predictive quantizer approach based on the PNG-lters together with an open-source compression algorithm. Both compression and decompression can be adapted for asynchronous and multi-threaded execution.