Forensic Uses of Digital Imaging

Published:
Author(s):

Purchasing Options

Hardback
$119.95
Add to cart
ISBN 9780849309038
Cat# 0903
 

Features

  • Shows proper use of image processing and the most common errors by giving examples of digital images
  • Presents examples of artifacts produced in digital imaging that will be useful to both users and counsel
  • Describes examples and procedures derived from a wealth of personal experience in both civil and criminal trials
  • Illustrates ways that questions and answers can explain how these methods can be and have been used and abused, and how to communicate these facts to a jury
  • Organizes topics in an easily accessible format for quick reference
  • Lavishly illustrated - includes 16 pages of color photos
  • Summary

    It happens all too often: The vague images of a poor quality video from a surveillance camera splash across the screen in a darkened courtroom and the guilt or innocence of the defendant hinges on whether or not the jury can determine if he or she is really the person in those images. Interpretation and misinterpretation of information about imaging in general, and digital image manipulation in computers in particular, by expert witnesses on both sides, and by counsel who ask questions that are both confused and confusing, may or may not help the jury in reaching a decision. Clearly there is a need for a simple guide to digital imaging for law and forensic professionals.
    Forensic Uses of Digital Imaging addresses that need. Written by the author of the best selling Image Processing Handbook, it shows you step-by-step how to use digital imaging to its best advantage. It explains by example when and why some procedures are appropriate and what they can be expected to reveal. While other books discuss computer programming to implement algorithms, this book shows in more simple terms just what the advantages and shortcomings of digital imaging are, and how computer image processing can be used to enhance the ability to access detail without compromising the truth of images.
    Practitioners will learn how to testify about their procedures and results in simple, precise language. Counsel will discover appropriate avenues for questioning to bring forth such explanations, and how to challenge witnesses who may confuse or mislead juries with wrong information or opinions.

    Table of Contents

    Digital Cameras and Forensic Imaging
    Introduction
    Why go digital?
    Uses of digital imagery
    Film as a light sensor
    Tonal and spatial resolution, and their consequences
    Color response
    Digital photography
    Maintaining chain-of-control with digital images
    Digital video
    Scanners
    Taking good pictures
    Presenting pictures in the courtroom
    Summary
    Processing Digital Images
    Noise in digital images
    Noise reduction methods
    Median filtering
    Processing color images
    Nonrandom noise
    Adjusting contrast, brightness and gamma
    Adjusting color balance
    Adjusting size (magnification)
    Spatial distortions
    Other applications
    Enhancement
    Enhancement of detail
    Sharpening
    Sharpening color images
    Other enhancement techniques
    Less common processing methods
    Color separation and filtering
    Frequency space (Fourier processing)
    High and low pass filtering, band-pass filtering, and periodic noise
    Deconvolution, or removal of system defects
    Measuring image resolution
    Resolution from the Fourier transform
    Tonal (gray scale) resolution
    Detecting compression
    Detecting forgeries
    Maintaining records
    Identification
    The imaging chain
    Surveillance video cameras
    Recording and playback problems
    Pixels and resolution elements
    Noise and tonal resolution
    Other shortcomings
    Enhancement
    Image restoration
    Recognition and identification
    Identification of faces
    Identification by DNA
    Misdirection and mistakes
    The expert witnesses
    Working with counsel, judges and juries

    Related Titles