LamTangYu

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Introduction

The purpose of the camera forensics project is to automatically detect whether an image, that was produced by CFA interpolation, was tampered with. CFA interpolation is used by digital camera to generate digital images. The interpolation will result in specific statistical patterns in the pixels of an image, which and then be utilized to determined whether or not an image has been altered.

Background

What is CFA Interpolation?

When digital cameras capture images, it saves the output of a single sensor after passing through a color filter array (CFA). Every single pixel of a color image is composed of three color channels, red, green, and blue. However, the camera is only able to sample a single color channel per pixel, so to fully form a colored image, the values of the other two colors will have to be estimated. Various interpolation techniques are used to estimate the missing samples.

Different Types of CFA Interpolation Techniques

File:Bayer pattern on sensor.svg

The Bayer arrangement of color filters on the pixel array of an image sensor

A common CFA is the Bayer Array.

References - Resources and related work

References

Software

Appendix I - Code and Data

Code

File:CodeFile.zip

Data

zip file with my data

Appendix II - Work partition (if a group project)

Brian and Bob gave the lectures. Jon mucked around on the wiki.