Robust Super-Resolution for Mixed-Resolution Multiview Image Plus Depth Data

Increasing spatial resolution and thus improving the image quality is a key issue in the mixed-resolution multiview image and video processing domain. Given adjacent camera perspectives with various spatial resolutions and their corresponding depth information, the high-frequency part of a high-resolution view can be used for increasing the image quality of a neighboring low-resolution camera perspective. However, a reasonable projection of high-frequency information onto the image plane of a neighboring low-resolution view typically requires pixel-wise error-free depth data for the high-resolution reference image. Starting from this, a novel image super-resolution approach is proposed that is robust against both inaccurate depth acquisition and nonperfect calibration of spatially low-resolution depth sensors. The algorithm is based on displacement-compensated high-frequency synthesis and aims at correcting the projection errors introduced by inaccurate depth information. The proposed approach is further effectively extended by a signal extrapolation technique. For a wide range of proper scenarios, the proposed framework achieves substantial objective and visual gains compared with the considered reference approaches. The improvement of quality is shown for both simulated and self-recorded experimental data.