Guided depth image reconstruction from very sparse measurements

Abstract

Depth images captured from modern depth cameras generally suffer from low spatial resolution, noise, and missing regions. These kinds of images cannot be used directly in applications related to depth images, e.g., robot navigation, 3DTV, and augmented reality, which basically need high-resolution input images with no noise o missing regions to function properly. To address the problem of low spatial resolution, noise degradation, and missing regions in depth images, we propose methods based on a guidance color image for depth reconstruction (DR) from sparse depth inputs and depth image super-resolution (SR). We also suggest a scenario wherein these problems can be integrated and addressed simultaneously. Further, we also demonstrate applications of the proposed approach for depth image denoising and depth image inpainting. In our approach, the guidance color image is used for obtaining the segment cues by applying mean-shift (MS) or simple linear iterative clustering (SLIC) segmentation on it. These strong segment cues help in aiding the DR and SR problems by considering the corresponding segments in the input depth image, and estimate the unknown pixels by either plane fitting or median filling approaches. Furthermore, we explore both direct and pyramidal (hierarchical) approaches for SR and DR-SR for higher upsampling factor. As such, our approaches are relatively simpler than some of the contemporary methods, yet the experimental results of the proposed methods show superior performance as compared with some other state-of-the-art DR and SR methods.