The proliferation of digital video recording systems (DVRs) in our society presents significant challenges to law enforcement when attempting to obtain visual evidence of a crime. Proprietary digital recording technology and a lack of interoperable standards in the CCTV Industry, means that no single Standard Operating Procedure or process can be referenced for the acquisition of all Digital Multimedia Evidence (DME).
First Responders, Digital Evidence Specialists, Forensic Video Analysts and Technicians require specialized equipment, skills, knowledge and training to ensure that DME is protected and that Best Evidence is recovered and preserved. Data that is commonly exported from DVR systems are often wrapped in any one of a number of digital video containers or players. Many of the players are referred to as “Open Source” and allow easy viewing of the data in most computer systems. However, ‘Open Source’ players and containers, such as those identified by file extensions with .WMV, .AVI, .AFS, etc., often indicate that the visual quality of the evidence has been reduced from its original form. The goal of this document is to guide the investigator through Best Practices to ensure that best evidence is the target of DME acquisition and that the integrity of the original data is maintained.
- multiplexed decoding
- image stabilization
- frame averaging
- automatic image tracking
- time lapse and real-time video analysis
- image enhancement techniques
- digital video recovery & analysis
- videotape repair & authentication
- legal issues & courtroom testimony
- photographic / video comparison