Massively parallel GPU computing for fast stereo correspondence algorithms

Abstract

A GPU-based implementation of the fixed window partially demosaiced CFA stereo matching application is presented.Accelerations up to 20 times are obtained for large size image pairs.A GPU-based implementation of the adaptive window color stereo matching application is presented.It can handle four pairs of standard images from Middlebury database within roughly 100 ms.A comparative study among different GPU-based local dense stereo matching implementations is provided. Current accurate stereo matching algorithms employ some key techniques that are not suitable for parallel GPU architecture. It will be tricky and cumbersome to directly take these techniques into GPU applications. Trying to tackle this difficulty, we design two GPU-based stereo matching algorithms, one using a local fixed aggregation window whose size is configurable, and the other using an adaptive aggregation window which only includes necessary pixels. We use the winner-takes-all (WTA) principle for optimization and a plain voting refinement for post-processing; both do not need complex data structures. We aim to implement on GPU platforms fast stereo matching algorithms that produce results with same-level quality as other WTA local dense methods that use window-based cost aggregation. In our GPU-based implementation of the fixed window partially demosaiced CFA stereo matching application, accelerations up to 20 times are obtained for large size images. In our GPU-based implementation of the adaptive window color stereo matching application, experiment results show that it can handle four pairs of standard images from Middlebury database within roughly 100 ms.