Robust stereo matching with fast Normalized Cross-Correlation over shape-adaptive regions

Normalized cross-correlation (NCC) is a common matching technique to tolerate radiometric differences between stereo images. However, traditional rectangle-based NCC tends to blur the depth discontinuities. This paper proposes an efficient stereo algorithm with NCC over shape-adaptive matching regions, producing depth-discontinuity preserving disparity maps while remaining the advantage of robustness to radiometric differences. To alleviate the computational intensity, we propose an acceleration algorithm using an orthogonal integral image technique, achieving a speedup factor of 10~27. In addition, a voting scheme on reliable estimates is applied to refine the initial estimates. Experiments show that, besides the robustness, the proposed method obtains accurate disparity maps at fast speed. Our method highly ranks among the local approaches in the Middlebury stereo benchmark.