| PhD Seminar

Name of the Speaker: Mr. Sumit Sharma (EE20D042)
Guide: Dr. Kaushik Mitra
Online meeting link: https://meet.google.com/gkd-tuby-zrj
Date/Time: 18th December 2024 (Wednesday), 10:30 AM
Title: Transforming Single Photon Camera Images to Color HDR Images

Abstract :

Traditional CMOS sensors suffer from restricted dynamic range and sub optimal performance under extreme lighting conditions. They are affected by electronic noise in low light conditions and pixel saturation while capturing high illumination. Recent High Dynamic Range (HDR) Imaging methods, often designed for CMOS Sensors, attempt to address these issues by fusing multiple exposures. However, they frequently introduce artifacts like ghosting and light flickering in dynamic scenarios and non-uniform signal-to-noise ratio in extreme dynamic range conditions. Recently, Single Photon Avalanche Diodes (SPADs) , also known as Single Photon Camera (SPC) sensors, have surpassed CMOS sensors due to their capability to capture individual photons with high timing precision. Unlike traditional digital cameras that first convert light energy into analog electrical currents and then digitize them, SPAD sensors perform direct photon detection, making them less susceptible to extreme illumination conditions. Their distinctive non-linear response curve aids in capturing photons across both low-light and high-illumination environments, making them particularly effective for High Dynamic Range Imaging. Despite their advantages, images from SPAD Sensors are often noisy and visually unappealing. To address these challenges, we evaluate state-of-the-art architectures for converting monochromatic SPAD images into Color HDR images at various resolutions. We present a two-stage approach i.e.,

1. Transforming monochromatic SPAD images into color images via Image2Image translation networks and second enhancing these Color images to achieve Color HDR via Single Image HDR Methods.

2. Single Stage approach i.e., transforming monochromatic SPAD HDR Images to Color HDR Images.

Our evaluation involves both qualitative and quantitative assessments of these architectures, focussing on their effectiveness in each stage of the conversion process.