Phase-Guided Light Field 3D Imaging with High Pixel Resolution

On 3D imaging, light field cameras are typically single-shot. However, they often suffer from low spatial resolution and limited depth accuracy. In this paper, by employing an optical projector to project a group of high-frequency phase-shifted sinusoid patterns, we propose a phase-guided light field algorithm to significantly improve both the spatial and depth resolutions for off-the-shelf light field cameras. First, in order to correct the axial aberrations caused by the main lens of our light field camera, we propose a deformed cone model to calibrate our structured light field system. Second, over wrapped phases computed from patterned images, we propose a stereo matching algorithm, i.e. phase-guided sum of absolute difference, to robustly obtain the correspondence for each pair of neighbored two lenslets. Finally, based on the reference depth by phase-guided stereo matching, we conduct a re-projection and refinement strategy to reconstruct 3D point clouds with spatial-depth high resolution. Experimental results demonstrate that, compared to existing active light field and temporal phase unwrapping methods, the proposed method achieves better performance in both spatial resolution and frame rate. It reconstructs 3D point clouds with a spatial resolution of 1280×720, achieving a 10× improvement, while requiring only a single set of high-frequency patterns.