Real-time Dense Disparity Estimation based on Multi-Path Viterbi for Intelligent Vehicle Applications

This paper proposes a new real-time stereo matching algorithm paired with an online auto-rectification framework. The algorithm treats disparities of stereo images as hidden states and conducts Viterbi process at 4 bi-directional paths to estimate them. Structural similarity, total variation constraint, and a specific hierarchical merging strategy are combined with the Viterbi process to improve the robustness and accuracy. Based on the results of Viterbi, a convex optimization equation is derived to estimate epipolar line distortion. The estimated distortion information is used for the online compensation of Viterbi process at an auto-rectification framework. Extensive experiments were conducted to compare proposed algorithm with other practical state-of-the-art methods for intelligent vehicle applications.