50 research outputs found
Coarse-to-Fine Lifted MAP Inference in Computer Vision
There is a vast body of theoretical research on lifted inference in
probabilistic graphical models (PGMs). However, few demonstrations exist where
lifting is applied in conjunction with top of the line applied algorithms. We
pursue the applicability of lifted inference for computer vision (CV), with the
insight that a globally optimal (MAP) labeling will likely have the same label
for two symmetric pixels. The success of our approach lies in efficiently
handling a distinct unary potential on every node (pixel), typical of CV
applications. This allows us to lift the large class of algorithms that model a
CV problem via PGM inference. We propose a generic template for coarse-to-fine
(C2F) inference in CV, which progressively refines an initial coarsely lifted
PGM for varying quality-time trade-offs. We demonstrate the performance of C2F
inference by developing lifted versions of two near state-of-the-art CV
algorithms for stereo vision and interactive image segmentation. We find that,
against flat algorithms, the lifted versions have a much superior anytime
performance, without any loss in final solution quality.Comment: Published in IJCAI 201