In today’s technological world, video surveillance cameras and smartphones are ubiquitous, and the footage captured by them can be crucial in investigations.

A clean video source is generally more effective for video enhancement. Investigators should preferably import a video in its original captured format, i.e., transfer it directly from the camera or sensor. However, if the video is transcoded or not clear enough to evidently depict the event, forensic image and video enhancement solutions may be used to increase the clarity. Forensic video enhancement is a scientific method/technique that helps in maximizing the quality and clarity of recorded video footage that serves as evidence while maintaining its integrity for use in a court of law. However, the challenge is to maintain its integrity while maintaining the highest level of clarity and visibility.

The purpose of this blog is to go over some of the forensic video enhancement methods and techniques that a forensic video analyst may apply during a digital forensics investigation, as well as some of the challenges that digital forensic experts come across.

Forensic Video Enhancement Techniques:

During the digital video enhancement process, it is imperative that the expert uses the proper methodologies and that the original recording is in good condition. The following techniques can assist a forensic video analyst during this process.

1. Histogram Equalization

Histogram Equalization is a contrast-enhancing method by uniformly distributing the pixel values. It adjusts the image tones by distributing the pixel values more uniformly across the available range. Also, it helps in optimizing the specific region of the image.

2. Contrast Brightness

Adjusts the contrast and brightness values of the image. It maps input image values to output image values according to a linear transformation. The mapping involves two operations: multiplication and addition, with constants controlled respectively by the Contrast and Brightness parameters. Images that are underexposed or overexposed can be improved using contrast brightness control.

3. Deinterlacing

Converts interlaced videos into progressive ones. It supports several options to choose active fields, their order, and the interpolation method. In an interlaced video, two subsequent fields are stored in every frame: the first in the even-field and the second in the odd-field, or vice versa. Being that the image coordinates are zero-based, the even field is the top one. Even lines are discarded from the odd field, while odd lines are discarded from the even field.

4. Demultiplexing

A demultiplexer separates combined video signals into individual instances. Multiplexed video files (files with video streams from multiple cameras intertwined together) can be separated into individual camera views using this technique, making forensic video analysis easier.

5. Noise Reduction & Video Denoising

The clarity of the footage can be severely impacted by a variety of events that happen during the acquisition of the video, such as noise. It enhances the smoothness, i.e., the amount of noise or texture of the final image, by fine-tuning the processing algorithms. Noise Reduction & Video Denoising are accomplished using a variety of sophisticated techniques.

6. Sharpening

Sharpening enhances the image details. Depending on the nature of the image, Laplacian sharpening and unsharp masking are typically used. The Laplacian Sharpening filter convolves the image with a 3×3 Laplacian kernel and then adds the resulting high-passed image onto the original image. While the Unsharp Masking, emphasizes the contrast of small details (edges of objects) in the video frame.

7. Stabilization

It means stabilizing the video frames. The stabilization enhancement allows to tune the algorithms used to reduce shaking and unwanted movement in the video. There are times when the video that was captured is not smooth. Techniques or methods for video stabilization can be used in this situation. It makes the video play as smooth as possible by minimizing movement. The goal of video stabilization is to increase the consistency and stability of the recorded video footage.

8. Motion Detection

By examining the variations in a sequence of photos, motion detection can identify movement in a scene. Motion detection locates events of interest in a video quickly by simply pausing on frames with motion. One can restrict detection to a certain region of the image. In order to make the results more robust, a background image is generated for comparison by multiple frames and a denoising filter is applied.

Challenges encountered in Video Forensics by Digital Forensics experts:

Forensic Video Analysis is not always a smooth process, and there are several barriers that need to be overcome. During the process, digital forensic experts may face a number of challenges, including but not limited to those listed below.

1. When working with low-quality footage, identifying a person, licence plate, or anything similar can be quite difficult. However, because of digital compression, it is challenging to read the details.

2. As technology has advanced, it is now much simpler to use video manipulation techniques. As a result, it can also be said that the legality and authenticity of such video evidence are constantly in doubt. Consider deepfakes.

3. Video evidence must be scraped for every minute of incriminating information. However, if human rights are violated, the video evidence may not be used as evidence in court. A clear example is the right to privacy.

4. Preventing data from being altered or stolen online is crucial. This can also be seen as a hurdle because it is vital to do so on disconnected, internet-free devices to prevent tampering with the video evidence.

5. In some cases, the video is captured in an unsteady manner if there are a lot of motions or noises nearby. The issue with this is that it is difficult to locate the evidence.

6. If the object in question is beyond the range of the camera, obtaining any clarity is a difficult task.

For forensics video enhancement, Amped FIVE is often used by qualified forensics experts globally.

Evidence of a crime’s motive and identity can be concluded using video footage and images gathered during the course of the investigation. These sources have become crucial in criminal investigations.

However, the quality of the video is crucial in these processes and can be a game-changer in criminal cases. In the absence of proper forensic video enhancement, recorded footage may result in inferior quality due to various reasons like inadequate lighting, the angle of the video, the speed of the recording, or adverse weather conditions. Users can therefore enhance and disclose information hidden in video and image evidence by using Amped FIVE.

This software is the most complete image and video analysis software for managing the entire workflow, from conversion to analysis, enhancement, redaction or spotlight, and report generation. It ensures an accurate, repeatable, and reproducible scientific procedure with its workflow and documentation.

Amped FIVE is the most comprehensive picture and video forensics programme, known for its dependability and productivity. With more than 140 filters and tools, it is an all-in-one solution that is specifically made for forensics, public safety, and national security. It can convert, process, improve, analyse, present, and document images and videos.

It supports many different picture and video data that is obtained from different multimedia sources, such as CCTV and DVR systems, body worn cameras, dash cameras, drones, mobile phones, fingerprint scanners, documents, and much more. The software also supports audio streams from these sources. According to end user requests, support for hundreds of proprietary video file types is regularly upgraded.

Amped FIVE offers the capacity to stabilize unsteady movies, fix blurred details, or alter noise and lighting concerns through a rational and nondestructive procedure. Specialized functions are also available, including super resolution, redaction, photogrammetry, optical distortion and aspect ratio correction, perspective correction, and alignment in numerous frames.

Key Features:

• Load images, videos, and hundreds of proprietary CCTV/DVR formats
• Automatically produce a thorough scientific report.
• Produce video presentations with audio and redacted frames.
• Analysing and Interpreting file data and structure
• Restore and improve to make licence plates, objects, and faces more clear

Conclusion:

Despite the fact that surveillance techniques are more widely used and simpler to use than ever before, environmental elements can have an impact on the quality of the footage that is collected. With modern technology, it is possible to enhance the quality of the video without jeopardizing the validity of the evidence.

Forensic can still achieve impressive results with videos that have been transcoded or have had their frame rates modified, but improving a clean source will yield the finest results.