Digital Video Forensics: Uncovering the Truth in a World of Distorted Realities
Video Analysis – Content Authentication – Tamper Detection
In this course, the participants will gain a comprehensive understanding of the digital video forensics domain, beginning with the fundamental concepts of digital videos and the technical issues related to digital video processing, to the basic knowledge of wide range of issues associated with the evidential use and forensic analysis of video evidence, followed by the practical knowledge of various video forensic investigation procedures (including both rudimentary and specialized video content authentication and forgery detection scheme), all of which will help develop crucial analytical, problem-solving, and research skills. The participants will also gain a deep understanding of the current research gaps, open issue and future research avenues in the video forensics domain, which will act as a platform for further career and personal development. Altogether, this course will enable the participants to establish a strong foundation for the eventual development of a meaningful career in the tremendously exciting domain of video forensics.
Ever since the invention of photography, digital visual media has continued to play a pivotal role in shaping our community’s belief system by continually affecting our perception of reality. Aside from satisfying their usual recreational purposes, digital images and videos have been providing investigative benefits by serving as an evidence repository that can be used for post-incident analysis for quite some time now. In the court of law, digital videos are increasingly being used as evidence. But as with any technology that is powerful enough to affect society’s belief system, visual media too is far from immune to malicious manipulations and alterations. While the innate vulnerability of digital videos to unobtrusive alterations causes us to become skeptical of their validity, their usefulness in today’s world remains incontrovertible, and in sensitive areas where their use is unavoidable, reliance on manipulated data could be detrimental. It is, therefore, crucial to validate the integrity of digital videos prior to the acceptance of their contents as an accurate depiction of reality.
Course is self-paced
18 CPE Credits
What will you learn?
The course aims to provide the participants with a comprehensive understanding of the digital video forensics domain. The participants will gain:
- A fuller understanding of the fundamentals of digital videos and the technical issues related to digital video processing. This information will help build a strong foundation for the entire course.
- The knowledge of a wide range of issues associated with the evidential use and forensic analysis of video evidence, including the basic principles of collection, recovery, enhancement, analysis, and interpretation of video evidence, and the essential considerations related to the admissibility of video evidence in court.
- An overview (in the form of case-studies) of the current state of affairs with regards to actual instances of use of digital videos as evidence within and beyond the justice system, along with a brief study of actual cases of content tampering.
- A detailed understanding of the basic concepts and methods of operation of contemporary video forensic technologies, including both rudimentary and specialized video content authentication and forgery detection schemes.
- A thorough understanding of the current research gaps, open issue and future research avenues in the video forensics domain, which will act as a platform for further career and personal development.
What skills will you gain?
Upon completion of the course, the participants will have acquired:
- A firm grounding in the digital video forensics domain.
- Complete understanding of the video forensics process, starting from the collection of video data to the actual use of this data as forensic evidence.
- Practical knowledge of various video forensic investigation procedures, which will help develop crucial analytical, problem-solving, and research skills.
- A strong foundation for the eventual development of a meaningful career in the video forensics domain.
After the completion of the course, the participants will be able to perform comprehensive analysis of digital videos from an entirely forensic standpoint. They will learn to distinguish natural videos from the manipulated ones, and will understand how each tamper operation affects the underlying attributes of a given video. Moreover, they will be able to determine which forensic artifact works best for the revelation of which kind of tamper operation, which will in turn enable them to select the most appropriate forensic artifacts for the task at hand.
The knowledge gained from this course and the skills acquired therefrom will be apposite to researchers and practitioners, as well as forensics analysts, investigators, and expert witnesses.
What will you need?
- Laptop or desktop with Internet connectivity
What should you know before you join?
- Familiarity with computer image and video files
- Familiarity with installing computer based software from a website
- Basic programming skills
Raahat Devender Singh is a PhD research scholar and a guest lecturer working in the Department of Computer Science and Engineering in University Institute of Engineering and Technology, and the Forensics Department in Panjab University, Chandigarh, India. She has been actively working in the Digital Video Forensics domain for over three years, and her fields of specialization include digital signal processing, digital image and video content authentication and forgery detection, and forensic analysis and interpretation of digital visual media evidence. She has participated in a number of national and international conferences, and has written several articles and research papers for magazines and scientific journals of various publishing houses including Springer, World Scientific, and Elsevier.
Digital Video Forensics
Fundamentals of Digital Videos and Digital Video Processing
This module covers the fundamentals of digital videos and digital video processing. Coverage includes an overview of the digital video capture process, spatio-temporal sampling, motion estimation, and video encoding. Basic concepts related to digital videos including frame-rate, bit-rate, resolution, visual quality, data losses and impairments, and important video processing operations including noise reduction and compression are covered. This module also presents a succinct analysis of different kinds of digital videos, where the categorization is based on the kind of acquisition device, recording parameters and environmental conditions prevalent during the acquisition process. Please note that the primary objective of this module is to familiarize the participants with those aspects of digital videos and digital video processing which would be useful to them from a forensic standpoint.
Module 1 covered topics:
- Overview of basic concepts of digital videos: Video capture process, spatial and temporal sampling, motion estimation, frame-rates and bit-rated
- Video encoding standards and formats
- Overview of technical issues related to video recordings: Data losses and impairments, visual distortions and artifacts, video quality evaluation metrics
- Various categories of digital videos, based on the kind of recording device, placement of the camera, mode of capture, and environmental conditions at the time of recording
Module 1 exercises:
- Knowledge test (consisting of true or false type questions, multiple choice and reverse multiple choice questions, and crossword puzzle)
Video Evidence: Basic Concepts and Principles
This module presents a detailed account of the origin and history of digital videos in regards to their role as forensic evidence, including the impact of CCTV on modern day surveillance. To help illustrate the significance and inculpatory nature of video evidence, the module provides examples of real-life cases of use of video evidence during criminal investigations and court proceedings. Real-life instances of footage tampering and basic principles and issues related to content authenticity and admissibility are also discussed, along with a thorough analysis of the principles and procedures involved in the collection, recovery, enhancement and authentication of forensic evidence.
Module 2 covered topics:
- Digital videos as forensic evidence and impact of CCTV
- Video evidence: Within and beyond the justice system
- Instances of use of video evidence in criminal investigations and litigations
- Concerns regarding content trustworthiness and examples of suspected footage tampering
- Admissibility of video evidence: Principles of general acceptance, issues and concerns
- Principles of forensic video analysis: collection, recovery, enhancement, analysis and interpretation of video evidence
Module 2 exercises:
- Knowledge test
- Mini-case studies
- Scenario-based exercises
Content Authentication and Tamper Detection in Digital Videos: Part 1 (Basic)
This module begins with an exposition of the basic concepts and principles of digital video authentications, followed by a detailed analysis of the domain of source camera identification, and the study of rudimentary content authentication measures such as timestamp analysis, digital signatures and watermarks. This is followed by exploration of some simple integrity verification schemes including hash value analysis, metadata and hex editor analysis, and dubbed video test. The limitations of all the aforementioned schemes will also be evaluated.
Module 3 covered topics:
- Active and passive, blind and non-blind forensics: Brief overview
- Source camera identification
- Active-non-blind methods of content authentication and their limitations:
- Timestamp analysis
- Watermarks and digital signatures
- Passive-blind/basic integrity verification schemes and their limitations:
- Hash value analysis
- Metadata analysis
- Hex editor analysis
- Dubbed video test
Module 3 exercises:
- Knowledge test
- Practical experiments
Content Authentication and Tamper Detection in Digital Videos: Part 2 (Advanced)
Module 4 description: This module covers advanced topics related to digital video forensics, beginning with the study of various types of video forgeries, followed by thorough analysis of specialized forgery detection techniques and various forensic artifacts utilized by these techniques. Coverage also includes a comprehensive study of the issues, challenges and future research avenues in the domain of digital video forensics.
Module 4 covered topics:
- Types of video forgeries
- Specialized passive-blind forgery detection techniques:
- Error Level Analysis
- Re-compression and transcoding detection
- Detection of frame-based tampering (frame-insertion, frame-removal, frame-replication/duplication, and frame-shuffling)
- Detection of copy-paste/splicing and upscale-crop forgeries
- Current research issues and challenges, future research avenues
Module 4 exercises:
- Knowledge test
- Scenario-based exercises
- Practical experiments
If you have questions, feel free to contact our course coordinator Marta at [email protected]