Book Image

Learning Python for Forensics

By : Chapin Bryce
Book Image

Learning Python for Forensics

By: Chapin Bryce

Overview of this book

This book will illustrate how and why you should learn Python to strengthen your analysis skills and efficiency as you creatively solve real-world problems through instruction-based tutorials. The tutorials use an interactive design, giving you experience of the development process so you gain a better understanding of what it means to be a forensic developer. Each chapter walks you through a forensic artifact and one or more methods to analyze the evidence. It also provides reasons why one method may be advantageous over another. We cover common digital forensics and incident response scenarios, with scripts that can be used to tackle case work in the field. Using built-in and community-sourced libraries, you will improve your problem solving skills with the addition of the Python scripting language. In addition, we provide resources for further exploration of each script so you can understand what further purposes Python can serve. With this knowledge, you can rapidly develop and deploy solutions to identify critical information and fine-tune your skill set as an examiner.
Table of Contents (24 chapters)
Learning Python for Forensics
Credits
About the Authors
Acknowledgments
About the Reviewer
www.PacktPub.com
Preface
Index

Introduction to EXIF metadata


EXIF metadata is a standard used for image and audio file tags created by devices and applications. Most commonly, this kind of embedded metadata is associated with JPEG files. However, EXIF metadata is also present in TIFF, WAV, and other files. In JPEG files, EXIF metadata can contain technical camera settings used to take the photo as the shutter speed, F-stop, and ISO values.

These may not be inherently useful to an examiner, but tags containing the Make, Model, and GPS location of the photo can be useful for attributing an individual to a crime. Each of these elements are associated with a tag. For example, the "Make" metadata is EXIF tag 271 or 0x010F. A list of tags can be found at http://www.exiv2.org/tags.html.

EXIF metadata is stored at the beginning of JPEG images and, if present, is located at byte offset 24. The EXIF header begins with the hex 0x45786966, which is "Exif" in ASCII. The following is a hex dump of the first 52 bytes of a JPEG image.

Note...