The kinds and patterns of crimes that are being perpetrated nowadays clearly demonstrate how technology has an impact on crime. As technology has advanced, criminals have embraced a more contemporary method of committing crimes that do not include bodily damage, unlike traditional blue-collar crimes. In contrast to conventional crimes, today's criminals are very strategic and calculated in their planning, hence it is necessary to alter the methods of investigation used in order to effectively investigate these kinds of crimes.
The kinds of evidence that are retrieved these days to solve an investigation may also be used to illustrate the shifting trends in the patterns and kinds of crimes committed. The study and investigation of digital evidence, such as CCTV video, audio samples, images, and metadata analysis, accounts for over 60% of all evidence and necessitates the application of knowledge and proficiency in cutting-edge, unconventional technology.
To stay up with the rapid changes in the types of crimes being perpetrated today, forensic investigation's future now depends on using contemporary techniques to combat so-called "new age" crimes. Multimedia forensics can be seen as an area of forensics that concentrate on examination and scientific assessment of multimedia evidence –video, audio, and photographs.
Understanding Multimedia Forensics
One area of forensics that collaborates with computer forensics is multimedia forensics. Although The field of forensics that deals with using investigative methods to retrieve and preserve evidence from a digital device that has been turned over to a court of law is known as computer forensics. In contrast, multimedia forensics focuses on examining the evidence that has been retrieved. In order to preserve the integrity of the evidence, identify its source, and authenticate it, the analysis comprises a scientific assessment of the digital evidence.
Since technology is all around us as people, it is an essential element of who we are today. We are unable to function without our phones and laptops.
By extracting and analyzing digital fingerprints on digital evidence using innovative software that facilitates authentication and scientific examination of the same, multimedia forensics works to prevent and identify crime. The fact that digital evidence, such as images or audio or video recordings, used in criminal investigations, tends to not be authentic is frightening. In many cases, criminals alter the primary source's content in order to falsify the results of an investigation.
Therefore, it is a crucial first step to confirm and authenticate the presented evidence. Using technologies that facilitate the analysis, verification, and improvement of digital evidence is known as multimedia forensics.
As concerns about the integrity of the evidence presented to the court these days grow, there is a need for the same. Therefore, the authentication certificate that establishes the legal admissibility of digital evidence in a court of law is provided by multimedia forensic specialists to guarantee that the evidence is faithful to its nature.
Common Tools Used in Multimedia Forensics
Today's multimedia forensic specialists utilize a wide range of advanced techniques to analyze digital evidence. Tools such as Multispeech, FTK Imager, Acustek, Gold Wave, Computerized Speech Lab, Audacity, and others are frequently used for audio recordings that are submitted as evidence.
The tools serve a number of functions, such as separating the region of interest in audio samples, analyzing and authenticating data using histograms and LPC charts, and assisting in identifying evidence manipulation by comparing the obtained hash values from the source with the evidence that was submitted. Assessing the veracity of the evidence is further aided by metadata analysis and Hex value comparison. Nonetheless, the following are a few of the specific technologies utilized in multimedia forensics:
- Tools for image and video analysis: Used to find the alternation, additions, or deletions in multimedia information.
- Tools for network forensics: These are used to examine network traffic for indications of malicious behavior, like intrusion attempts or data exfiltration.
- Mobile forensics tools: Such tools are generally used to examine and retrieve data from mobile devices, like call logs, messages, and app information.
Techniques Employed in Multimedia Forensics
A variety of methods are used in multimedia forensics to examine and confirm the legitimacy of digital photos, videos, and audio data. These strategies fall into two general categories: aggressive and passive. Digital signatures and watermarking are examples of active techniques that need a known reference or authentication code. Passive techniques, on the other hand, focus on examining the fundamental features of the multimedia file itself.
Active Multimedia Forensics:
- Digital Watermarking: Adding a special code or signature to the multimedia file in order to confirm its legitimacy and original owner.
- Digital Signatures: Employing cryptographic methods to guarantee a digital file's validity and integrity.
- Active Authentication: Using a recognized authentication number for verification that is either transmitted with the picture or incorporated in it.
Passive Multimedia Forensics:
- Steganography: The process of concealing information in multimedia files that may be found and undone to expose the concealed data.
- Image Splicing Detection: This technique finds instances in which several photos have been merged to produce a single, modified image.
- Copy-Move Forgery Detection: This technique finds instances in which portions of an image have been duplicated and moved to different sections of the same picture.
- Statistical Analysis: Examining the picture or video's statistical characteristics to find irregularities or discrepancies.
- information Analysis: Looking for any alterations or manipulations by analyzing the information included in the multimedia file.
- Device Identification: Making an effort to connect the digital material to the device that produced it, such as a phone or camera.
Other Relevant Techniques:
- Reverse steganography: Recovering concealed information from multimedia files is known as reverse steganography.
- Video forensics: This field focuses on the scientific analysis and assessment of videos, including hidden data retrieval, camera identification, and tampering detection.
- Deleted File Recovery: Making an effort to retrieve erased files that could include important data.
- Live analysis: It is the process of examining a system's operational data in order to gather evidence in real time.
- Audio Analysis: Analyzing audio files to find alterations, such as those brought on by compression or audio editing software, is known as audio analysis.
- Deepfake Detection: Detecting modified photos and videos produced using deepfake technology is known as deepfake detection.
Tools and Techniques:
- Multimedia Forensic Tools are generally used to extract and examine multimedia evidence.
- Media Info is utilized in order to analyze the technical details of video or audio files.
- Forensic Software such as Magnet AXIQ or Cellebrite is used for data recovery and/or mobile forensics.
Challenges Faced by the Multimedia Forensic Experts
Multimedia forensic experts encounter several difficulties when analyzing digital evidence. Frequently, they are given unclear and disturbed audio and video samples, and the quality of the samples used for the investigation is so low that it is difficult for multimedia experts to extract information from these evidences. Additionally, there are instances where multimedia forensic specialists are given thousands of samples to examine. They are then required to go through each sample, find the area of interest where they believe they can extract some information, and then analyze it—a process that takes a great deal of patience and time.
Enhancing low-quality photos and videos to identify the culprit at the crime scene is the second major obstacle that multimedia professionals must overcome. The CCTV video given by the cameras is located distant from the crime site, and the photos presented for inspection are frequently of extremely low pixel resolution, making it challenging for the multimedia forensic professionals to piece together the events of the crime. Furthermore, it is well known that proper camera placement is crucial for efficient surveillance; in fact, in most cases, improper CCTV camera placement makes it difficult for specialists to identify the offender from the CCTV footage that is shown to the court.
The investigation of the 2011 Mumbai serial bomb blast case is a prime illustration of the difficulties that modern multimedia forensic specialists encounter. The CCTV footage was obtained from the crime site and presented to the court of law for examination. Among them was the automobile thought to be transporting the detonating agent that set off the explosion. Finding the number plate in the available public CCTV film was a significant difficulty for the multimedia forensic specialists.
However, the multimedia forensic specialists were unable to improve the number plate due to the extremely poor video quality and awkward camera placement. However, the Multimedia specialists looked at and reported on the other physical characteristics of the suspicious automobiles.
Future Trends in Multimedia Forensics
Advances in deep learning for identifying the source of multimedia, detecting manipulations, and analyzing artificial intelligence-generated synthetic material are some of the future prospects in multimedia forensics. Furthermore, forensic imaging and visualization methods are developing, making it possible to reconstruct crime scenes and model evidence in three dimensions. Additionally, cross-border cooperation and remote digital forensics are growing in popularity.
Here's a more detailed look at these trends:
1. Deep Learning and AI:
Source Identification: Artificial Intelligence (AI) can assist in determining the device or network that produced the multimedia information.
Deep Learning for Manipulation Detection: Deep learning algorithms are being used to detect subtle multimedia manipulations, including the insertion of phony information or the alteration of images or videos.
Analysis of Synthetic information: Multimedia forensics is creating techniques to identify and examine artificial intelligence (AI)-generated information, such as deepfakes, as it becomes more prevalent.
2. Forensic Imaging and Visualization:
Advanced Imaging Techniques: To produce intricate representations of photogrammetry, crime scenes and evidence, laser scanning, and aerial photography are being employed.
3D Modeling: To produce precise depictions of crime scenes and evidence that may be utilized in court, forensic specialists are utilizing 3D modeling.
Virtual reality and augmented reality are being investigated for use in forensic training, teaching, and crime scene investigation.
Conclusion
Multimedia forensics has emerged as a pivotal branch of digital investigation in response to the evolving landscape of modern crimes. As technology becomes increasingly integrated into everyday life, so too do criminal tactics evolve—shifting from traditional, physical crimes to more strategic and tech-savvy offenses. In this new era, digital evidence such as images, videos, and audio recordings plays a critical role in solving cases, necessitating the use of advanced tools and techniques to preserve, authenticate, and analyze such evidence with scientific precision.
The field leverages a wide array of methodologies, including both active and passive forensics, to validate the integrity of multimedia files. From detecting deepfakes and uncovering steganography to recovering deleted files and conducting live system analysis, multimedia forensics ensures that digital evidence presented in court is credible and tamper-proof. Despite facing challenges like poor-quality evidence and the sheer volume of data, experts continue to develop sophisticated solutions to overcome these barriers.
Looking ahead, the integration of artificial intelligence, machine learning, and 3D visualization promises to revolutionize the way digital evidence is interpreted and presented. As the digital realm continues to expand, multimedia forensics will remain a cornerstone of modern-day investigations—ensuring that justice is served through the meticulous and reliable analysis of digital footprints.