Accelerated hybrid image reconstruction for non-regular sampling color sensors

Increasing the spatial resolution is an ongoing research topic in image processing. A recently presented approach applies a non-regular sampling mask on a low resolution sensor and subsequently reconstructs the masked area via an extrapolation algorithm to obtain a high resolution image. This paper introduces an acceleration of this approach for use with full color sensors. Instead of employing the effective, yet computationally expensive extrapolation algorithm on each of the three RGB channels, a color space conversion is performed and only the luminance channel is then reconstructed using this algorithm. As natural images contain much less information in the chrominance channels, a fast linear interpolation technique can here be used to accelerate the whole reconstruction procedure. Simulation results show that an average speed up factor of 2.9 is thus achieved, while the loss in visual quality stays imperceptible. Comparisons of PSNR results confirm this.