Triple-Camera Setups for Image-Based Depth Estimation

Sammanfattning: This study was conducted as to attempt to find whether a three-camera setup could improve depth map retrieval as opposed to a two-camera setup. The study is based on three main ideas to exploit information from the additional camera. These are three cameras on one axis, as to exploit wide and short baseline benefits, three cameras on different axes, as to exploit vertical and horizontal scanning of the scene and a third idea of combining the two previous ideas. More than three cameras would impose particular implications on the solution and without sufficient theoretical justification thereof the study was limited to a study of the different three-camera configurations possible. As a practical connection was of interest, the study was further limited by the possibility to perform in real-time. An implementation based on previous research was made such as to evaluate images with specific scenes. Pre-processing by Census transformation of the images, camera calibration and rectification of different camera setups and optimizaton by the SGM algorithm are part of the solution used to retrieve results to analyse. Two tests were then studied, first one with rendered images and then one with images from real cameras. From these tests it was noted that a three-camera configuration can improve upon the results significantly and further, if the third camera was placed in perpendicular axis to the first camera pair, unique information was yielded which improves upon the result in specific cases. Using three cameras on the same axis showed no improvement when considering the error metrics BMP and BMPRE, but offers wider application uses, consistently providing better results than the worst pair.