Perspective rectification of integral images produced using arrays of circular lenses.

There are many different three-dimensional (3D) techniques to capture and deliver autostereoscopic 3D content. A promising technique that provides two-dimensional parallax as well as high-quality, full-color 3D content is integral imaging (InI). Misalignments between the lens arrays (LAs) and the camera charged coupled device, however, introduce geometric distortions in the acquired image that propagate through the different image processing stages and deteriorate the 3D effect. Here, we propose a method to accurately rectify the perspective distortion of integral images (InIms) generated using circular lenses. Using an edge-linking approach, we extracted elliptically shaped contours of elemental images in the perspectively distorted InIm. To calculate the rectification matrix, we used the images of the circular points. Subsequently, we applied a triangulation scheme followed by a statistical approach to accurately estimate the grid structure of the LA. Finally, we provided experimental results over a wide range of InIms to evaluate the robustness and accuracy of the proposed method using objective metrics.