NickNoahMegan

Introduction

The goal of our project was to gain an understanding of the modern state of demosaicing techniques and how to reduce demosaicing artifcats. We explore existing algorithms to discover their strengths and weaknesses, and implement some of them to improve our understanding. We also look into the future possibilities for the ISP by implementing the demosaicing portion of the DeepISP paper.

Background

Digital cameras use Color Filter Arrays (CFAs) such as a Bayer Filter to capture colored image data of the light entering the aperture. The image sensor is equally sensitive to any color of light, so a CFA blocks out all but one of the RGB colors so that we can capture a particular band of wavelengths at each pixel. This means each pixel only contains an R G or B value. We must fill in the blanks so every pixel contains all 3 color values. This is done through some form of interpolation. The absolute simplest approach is Nearest Neighbor, which just copies the value adjacent pixel of the same color channel. This is one of the less desirable approaches as it doesn’t take into account how colors should change across pixels. The most basic usable approach is Bilinear Interpolation.