Algorithm

World Wide Web

Computer security

Computer graphics (images)

The Internet

Set (abstract data type)

Computer science

Code (set theory)

Computer network

Decoding methods

Invisibility

Artificial intelligence

Encoding (memory)

Programming language

Web page

Channel (broadcasting)

Hyperlink

Computer vision

Key (lock)

Printed and digitally displayed photos have the ability to hide imperceptible digital data that can be accessed through internet-connected imaging systems. Another way to think about this is physical photographs that have unique QR codes invisibly embedded within them. This paper presents an architecture, algorithms, and a prototype implementation addressing this vision. Our key technical contribution is StegaStamp, a learned steganographic algorithm to enable robust encoding and decoding of arbitrary hyperlink bitstrings into photos in a manner that approaches perceptual invisibility. StegaStamp comprises a deep neural network that learns an encoding/decoding algorithm robust to image perturbations approximating the space of distortions resulting from real printing and photography. We demonstrates real-time decoding of hyperlinks in photos from in-the-wild videos that contain variation in lighting, shadows, perspective, occlusion and viewing distance. Our prototype system robustly retrieves 56 bit hyperlinks after error correction -- sufficient to embed a unique code within every photo on the internet.

StegaStamp: Invisible Hyperlinks in Physical Photographs