User-assisted inverse procedural facade modeling and compressed image rendering

Abstract

We take advantage of human intuition by encoding facades into a procedural representation. Our user-assisted inverse procedural modeling approach allows users to exploit repetitions and symmetries of facades to create a split grammar representation of the input. Terminal symbols correspond to repeating elements such as windows, window panes, and doors and their distributions are encoded as the production rules. Our participants achieved a compression factor that averaged 57% (min=12%, max=99%) while taking on average 7min (min=1, max=25) to compress an image. The compressed facades do not suffer from occlusion problems present in the input, such as trees or cars. Our second contribution is a novel rendering algorithm that directly displays the compressed facades in their procedural form by interpreting the procedural rules during texture lookup. This algorithm provides considerable memory savings while achieving comparable rendering performance.