Unsupervised extraction of coherent regions for image based rendering
Jesse Berent, Pier Luigi Dragotti · 2007
Image based rendering using undersampled light fields suffe rs from aliasing effects. These effects can be drastically reduced by usi ng some geometric information. In pop-up light field rendering [18], the scene is segmented into coherent layers, usually corresponding to approximately planar regions, that can be rendered free of aliasing. As opposed to the supervised method in the pop-up light field, we propose an unsupervised extractio n of coherent regions. The problem is posed in a multidimensional variational framework using the level set method [16]. Since the segmentation is done jointly over all the images, coherence can be imposed throughout the data. However, instead of using active hypersurfaces, we derive a semi-parametric methodology that takes into account the constraints imposed by the camera setup and the occlusion ordering. The resulting framework is a global multidimensional region competition that is consistent in all the imag es and efficiently handles occlusions. We show the validity of the method with some captured multi-view datasets. Other special effects by coherent reg ion manipulation are also demonstrated.