Forensic Video Enhancement
Video Forensic Experts will utilize many different steps and techniques while analyzing, evaluating, and enhancing video evidence. The first step in the process of forensic video enhancement is the receipt of evidence and preservation of the chain of evidence , which is also known as the chain of custody . Without establishing a proper chain of custody, a case’s evidence, and any work completed by the forensic expert, may be excluded and therefore not admissible in court. After arriving to NCAVF, the evidence is documented, logged into the evidence database, and copied to our servers so that it may be tracked and preserved indefinitely.
After copying the original evidence to our servers, the next step is to create an exact copy of the original video evidence in a format that is suitable for analysis and enhancement. Doing so protects the original evidence (thus preserving the chain of custody) while at the same time allows a new version to be adjusted during analysis.
During the initial analysis and evaluation of video evidence, a video forensic expert will be looking for many different things, such as:
- Size and resolution of the video
- Evidence of compression or conversion of the video (from original video format)
- Evidence of editing or adulteration
- Determination of video frame rate, codec, and other important details
- Analysis of Metadata or Exif Data
Once forensic experts have completed their initial evaluation and analysis of the video evidence, they will make determinations of what type of forensic video enhancement may be useful or even possible for the case. There are many factors that may affect how video evidence is enhanced, as well as to what degree the enhancement may be possible or useful, such as:
- Type of video recording equipment used
- Quality of digital camera or surveillance camera
- Settings of camera or DVR at the time of the incident
- Lighting conditions
- Night vision capabilities of the camera
- Camera angle
- Distance of the camera from the event, angle of the camera
- Video compression, export, etc.
After the proposed enhancements have been explained to the client, forensic experts will begin enhancing the video evidence. Utilizing state of the art computers and software, video forensic experts use many common enhancement techniques that are often useful to a case, they may include:
- Enlarging and/or zooming in on certain parts of a video
- Slowing down or speeding up a video
- Measuring heights, speed of objects, and people’s body movements
- Adjusting color, contrast, or other video qualities to better see what is happening
- Cleaning up video artifacts or distortion
- Syncing together multiple video angles from the same incident into one playable video
- Editing together multiple camera angles to show a cogent timeline of events
- Adding a time counter to identity individual frames
- Adding a counter to indicate the number of times something happens or is said
- Showcasing the time elapsed between specific events occurring in a video
- Identifying use of firearms, weapons, or other threatening actions by individuals in a video
Any enhanced videos, once completed, will be exported into a universally playable video format and renamed so that is is clearly an enhanced version of the original video. The enhanced video is not only high quality, but is able to be played on almost any brand of device -- such as any computer, tablet, or cell phone.
Writing a report and testifying in court or in deposition
Once enhancements have been completed for the case, it is sometime necessary for video forensic experts to write a detailed forensic report. This report is designed to be admitted into evidence, along with the enhanced video, as a written record of all findings and forensic video enhancement steps taken by the expert on both the original evidence as well as any enhanced videos created for the case. The amount and type of information included in the forensic report is customized to the specifics of the evidence as well as what is pertinent to each particular case.
Finally, forensic experts are often called upon to testify in depositions or court as to many details of the evidence. Sometimes the video expert will testify regarding observations and conclusions made regarding the evidence. Sometimes the expert will be called to testify regarding the method and tools used to enhance videos or audio created for the case. The forensic expert’s testimony can be to refute the findings of other forensic experts, or it can be solely in regards to explaining the enhancements. Whatever the situation, experts should be prepared to explain any and all aspects of the evidence for the judge or jury.