A Forensic-Grade Video Conversion Tool with Cryptographic Integrity Verification (V-CON-V)

Abstract

In this work V-CON-V (Video CONverter and Verifier), an integrity-centric automated video conversion and verification tool was developed to address the critical challenge of incompatible video evidence formats in forensic investigations in India. The system converts various heterogeneous and common video formatslike .dav, .avi, .mov, .mkv, .webm, .flv, .wmv, .3gp, .ogg, .mts, .ts into most acceptable standardized .MP4/H.264/AAC format while providing cryptographic proof of integrity preservation. A dual-hash approach also calculates hashes before and after conversion of the particular video format using SHA-256 which enables forensic practitioners to demonstrate in court of law that the converted file is a faithful representation of the original evidence. The system automatically produces in-depth PDF forensic audit reports containing file metadata, hash values and conversion logs which full fill the legal documentation requirements. Experimental evaluation on diverse real-world video datasets demonstrates a 99.9% successful conversion rate with complete integrity traceability and an average 22.2% storage reduction on 50 different video formats without perceptible quality degradation. The proposed system provides a robust, auditable and legally defensive video conversion solution for digital evidence preservation and analysis in implementation of the clauses of BNSS and BSA, 2023 in India.

Introduction

The rapid growth of digital video evidence from CCTV cameras, smartphones, surveillance systems, and other recording devices has created significant challenges for forensic investigations because videos exist in numerous formats that are often incompatible with forensic analysis software. Although many video conversion tools are available, they generally lack mechanisms to preserve evidence integrity, provide cryptographic verification, or generate legally admissible documentation. With the implementation of India's BNSS and BSA 2023, investigating agencies are now required to maintain secure recording, integrity preservation, audit trails, and hash verification for digital evidence throughout the legal process.

To address these issues, the authors propose V-CON-V (Video Converter and Verifier), a forensic-grade automated tool that converts eleven common and proprietary video formats into the standardized MP4 (H.264/AAC) format while maintaining evidence integrity. The system generates SHA-256 cryptographic hashes before and after conversion, automatically verifies file integrity, extracts metadata, and produces a detailed PDF audit report containing processing logs, hash values, timestamps, and legal compliance information suitable for court proceedings. Built using Python with open-source tools such as FFmpeg, SHA-256 cryptographic libraries, and FPDF, the software follows a five-stage pipeline comprising secure evidence acquisition, environment initialization, baseline hashing, forensic-grade video conversion, and post-conversion integrity verification with automated reporting.

The system is specifically designed to comply with BNSS and BSA 2023 by supporting secure evidence handling, maintaining chain of custody, and generating expert-ready documentation. Experimental evaluation using 50 real-world video files (44.2 GB) from CCTV footage, mobile devices, video cameras, and crime scene recordings demonstrated 99.9% successful conversion, 100% hash verification accuracy, 100% automated report generation, an average 22.2% storage reduction, and practical processing speeds of approximately 2.4× real-time. Compared with existing commercial and open-source video conversion tools, V-CON-V uniquely combines standardized video conversion, cryptographic integrity verification, automated legal reporting, and forensic compliance in a single platform, making it highly suitable for forensic laboratories, law enforcement agencies, and courtroom evidence preparation.

Conclusion

This paper introduced a digital evidence management critical problem-solving system, namely, V-CON-V which is an automatedvideoprocessingpipeline. Thesystemoffers a strong answer to the processing of forensic evidence by standardizingtheformat,verifyingthecryptographicintegrity, and their automated legal documentation mechanism thereby providing a powerful solution to the analysis of forensic evidence. Experimental assessment indicates that itis highly reliable (99.9% percentage) and stored significantly (22.2%percentcut)andentirelytraceableintermsofintegrity. With its alignment to the requirements of the legal frame- work, namely BNSS, to the requirements of the V-CON-Vforensic video evidence processing is a crucial step in the right direction, and the software is open-source, which givesit a high level of transparency and reproducibility, as well as provides it with a competitive edge over peers.

References

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Copyright

Copyright © 2026 Santosh Kumar, Subrato Sarkar, Asmita . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.