GDV — Concealed Messaging
A short payload is encoded into a cover image inside an ordinary-looking colour-correction app. The image travels through a standard messaging platform, is recompressed in transit, and arrives intact. The recipient extracts the message in the same app. No signal that a covert channel exists is visible to the platform or to an observer.
How it works
The covert mode is opened by a sequence of taps on the cover app's photo library. In this demo, tap the thumbnails in the order 4 → 2 → 1 → 3. Progress dots confirm each correct tap. Without the sequence, the app behaves as an ordinary colour-correction utility.
The message is encoded into the cover image using techniques described in the patent filings that are designed to survive standard image-platform recompression. The image can be sent inside the app directly, or exported and sent through any standard channel: WhatsApp, Signal, iMessage, Telegram, email, MMS.
Carrier platforms recompress images in transit. Short payloads — typically a few hundred bytes after error-correction — survive WhatsApp-class and Signal-class JPEG recompression, resizing, and EXIF stripping. The recipient opens the received photo in the same app, performs the activation sequence, and the message is recovered.
Capabilities
- Disguised application surface. The cover app presents as a routine utility. No visible indicator of a hidden mode.
- Gesture-based mode switching. Activation requires a specific interaction sequence indistinguishable from normal use.
- Carrier-platform agnostic. Works over any standard image-sharing channel. No platform cooperation required.
- Compression-survivable. Short payloads recover after one or more rounds of typical consumer-platform recompression.
- Silent failure. An extraction attempt with the wrong sequence or wrong cover yields no error and no observable signal.
- Optional in-app direct delivery. For closed-group deployments where carrier-platform routing is unnecessary.
Scope of this demonstration
This walkthrough visualises the user-facing workflow only. No real cryptographic or steganographic operations are performed in the embedded demo; the underlying encoding scheme is described in the patent. Realistic post-compression payload capacity is on the order of a few hundred bytes per cover image with error-correction. Key management, identity verification, and session establishment are not shown — a production deployment would layer these on standard vetted primitives.
Patent pending. Research demonstration. GDV-B · GB2608701.5.