Why are thermal images blurry

TL;DR

This paper investigates why thermal images are blurry and low-texture, revealing the physics behind ghosting effects, and proposes algorithms and hardware approaches to recover and enhance thermal image details.

Contribution

It provides a detailed explanation of thermal ghosting phenomena and introduces algorithms and a hardware approach to recover and enhance thermal image textures.

Findings

Spectral resolution improves texture recovery in thermal images.

Traditional thermal imaging fails to recover ground truth textures.

The proposed approach successfully enhances thermal perception in darkness.

Abstract

The resolution of optical imaging is limited by diffraction as well as detector noise. However, thermal imaging exhibits an additional unique phenomenon of ghosting which results in blurry and low-texture images. Here, we provide a detailed view of thermal physics-driven texture and explain why it vanishes in thermal images capturing heat radiation. We show that spectral resolution in thermal imagery can help recover this texture, and we provide algorithms to recover texture close to the ground truth. Using a simulator for complex 3D scenes, we discuss the interplay of geometric textures and non-uniform temperatures which is common in real-world thermal imaging. We demonstrate the failure of traditional thermal imaging to recover ground truth in multiple scenarios while our thermal perception approach successfully recovers geometric textures. Finally, we put forth an experimentally feasible infrared Bayer-filter approach to achieve thermal perception in pitch darkness as vivid as optical imagery in broad daylight.