Enhanced Spinning Parallelogram Operator Combining Color Constraint and Histogram Integration for Robust Light Field Depth Estimation

Accurate depth estimation is an essential part of most light field applications. Previous approach Spinning Parallelogram Operator (SPO) achieves robust depth estimation results in noisy and occluded scenes by fitting lines in Epipolar Plane Images (EPIs). However, only using histogram distances, SPO cannot handle complex occlusions and is sensitive to different parameters. In this letter, we propose enhanced Spinning Parallelogram Operator utilizing color constraint and histogram integration (SPO-CH) to address the above problems. The color consistency between different views is first introduced to exclude occlusions when measuring the histogram distances of occluded areas. We then design a novel Gaussian integration histogram that combines information from other adjacent bins, which improves the performances of noisy and texture-less scenes. Experimental results show that the proposed method effectively improves the depth estimation results. Comparisons with other state-of-the-art approaches show that the proposed method achieves better results for both synthetic and real-world images.