A client-side, air-gapped web application designed for digital forensic examiners to calculate CCTV temporal variance and synchronize video timelines. Engineered in compliance with LEVA video analysis protocols and SWGDE evidence recovery standards.
Access the live tool here: https://ryandus.github.io/SyncFlow/
(Accessible on mobile for live back-camera frame acquisition).
SyncFlow is built to operate in strict, isolated environments. The application executes 100% locally in the browser with zero server uploads, ensuring cryptographic chain-of-custody and data integrity for sensitive case files.
- Air-Gapped Processing: Zero-server architecture. All image processing, OCR, and cryptographic hashing (SHA-256) are performed entirely client-side using the Web Crypto API.
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Air-Gapped Reference-Time Calibration: Establishes true real-world reference time without external network connections by extracting trusted
DateTimeOriginalEXIF metadata from calibration photos taken with synced field devices, calculating temporal drift ($\Delta t$ ) entirely against client-side OCR DVR timestamps. - Touch-Optimized ROI Cropping: Precision crop tools with real-time contrast, grayscale, inversion, and binarization filters for clarifying degraded CCTV timestamps.
- Client-Side OCR (Tesseract.js): Real-time optical character recognition optimized for dot-matrix and 7-segment CCTV fonts with regex normalization.
- Clock-Drift Analysis: Calculates signed clock vectors (Δt), categorizing drift status (Fast/Slow/Synchronized), and computes quartz oscillator linear drift rates (seconds/day and PPM).
- Incident Timeline Synchronizer: Converts recorded video footage timestamps into calibrated real-world chronology.
- Court-Ready Evidence Exhibits: Generates standardized LEVA/SWGDE expert witness narrative statements and renders high-resolution PNG evidence cards for courtroom exhibit binders.
- Frontend: HTML5, Tailwind CSS, Vanilla ES6 JavaScript / TypeScript
- Metadata Parsing: ExifReader (DateTimeOriginal, GPS, camera hardware details)
- OCR Engine: Tesseract.js
- Exhibit Rendering: html2canvas
Since SyncFlow is entirely client-side, it can also be run locally without an internet connection.
- Clone the repository:
git clone https://github.com/ryandus/SyncFlow.git - Open
index.htmldirectly in any modern web browser. No local server required for core functionality.
SyncFlow is built for direct casework intake. Examiners can immediately input case identifiers, import calibration photographs or capture live DVR monitor displays, extract timestamps via local client-side OCR, and produce calibrated courtroom exhibits with cryptographic SHA-256 integrity verification.
Note: All generated exhibits include cryptographic hashes, EXIF hardware metadata, and embedded forensic watermarks for chain of custody verification.
Engineered by Ryan Hanks
SyncFlow joins a suite of open-source diagnostic and investigative web applications—including TriageFlow, TraceFlow, and the Police Report Generator—built to streamline technical workflows and maintain rigorous analytical standards.
This project is open-source and licensed under the MIT License.