The process by which an image is formed, processed, and displayed can be conceptualized as a chain of physical events called the imaging chain. By mathematically modeling the imaging chain, we can gain insight into the relationship between the camera design parameters and the resulting image quality. The mathematical models can also be used to optimize and assess the design of a camera for specific applications before expenditures are committed to building hardware.

Modeling the Imaging Chain of Digital Cameras teaches the key elements of the end-to-end imaging chain for digital camera systems and describes how elements of the imaging chain are mathematically modeled using the basics of linear systems mathematics and Fourier transforms. The emphasis is on general digital cameras designed to image incoherent light in the visible imaging spectrum. The reader will learn how digital camera design parameters are related to the elements of the imaging chain and how they influence the resulting image quality. The book also discusses the use of imaging chain models to simulate images from different digital camera designs for image quality evaluations.

This tutorial aims to help people interested in designing digital cameras who have not had the opportunity to delve into the mathematical modeling that allows understanding of how a digital image is created. My involvement with developing models for the imaging chain began with my fascination in the fact that image processing allows us to "see" mathematics. What does a Fourier transform look like? What do derivatives look like? We can visualize the mathematical operations by applying them to images and interpreting the outcomes. It was then a short jump to investigate the mathematical operations that describe the physical process of forming an image. As my interest in camera design grew, I wanted to learn how different design elements influenced the final image. More importantly, can we see how modifications to a camera design will affect the image before any hardware is built? Through the generous help of very intelligent professors, friends, and colleagues I was able to gain a better understanding of how to model the image formation process for digital cameras.

Modeling the Imaging Chain of Digital Cameras is derived from a course that I teach to share my perspectives on this topic. This book is written as a tutorial, so many details are left out and assumptions made in order to generalize some of the more difficult concepts. I urge the reader to pick up the references and other sources to gain a more in-depth understanding of modeling the different elements of the imaging chain. I hope that the reader finds many of the discussions and illustrations helpful, and I hope that others will find modeling the imaging chain as fascinating as I do.

Robert D. Fiete

October 2010