Anti-Aliasing Snapshot HDR Imaging Using Non-Regular Sensing

TL;DR

This paper introduces a novel snapshot HDR imaging sensor using non-regular pixel arrangements and Fourier domain reconstruction to achieve high dynamic range images free from aliasing artifacts.

Contribution

It proposes a non-regular pixel layout with spatially varying apertures and a Fourier domain reconstruction method for improved HDR imaging.

Findings

Effective high dynamic range imaging without aliasing artifacts.

Non-regular pixel arrangement mitigates spatial resolution loss.

Simulation results confirm high detail recovery in HDR images.

Abstract

Snapshot HDR imaging is essential to capture the full dynamic range of a scene in a single exposure, making it essential for video and dynamic environments where motion prevents the use of multi-exposure techniques or complex hardware set-ups. This work presents a snapshot HDR imaging sensor that is based on spatially varying apertures, implemented by combining two differently sized prototype pixels. The different light integration areas physically extend the dynamic range towards the lower end, compared to a standard high resolution sensor. A non-regular pixel arrangement is suggested, to mitigate aliasing and overcome a loss in spatial resolution that is associated with increased light integration area of the larger prototype pixel. Subsequent reconstruction in the Fourier domain, where natural images can be sparsely represented allows to recover the image with high detail. The image acquisition approach with the proposed non-regular HDR sensor is simulated and analysed with special emphasis on the spatial resolution. The results suggest the snapshot HDR sensor layout to be an effective way to acquire images with high dynamic range and free from aliasing artefacts.