Deep Data Hiding for ICAO-Compliant Face Images: A Survey

TL;DR

This survey reviews digital watermarking and steganography techniques for embedding tamper-evident signals into ICAO-compliant face images, enhancing post-capture security against morphing and deepfakes in identity verification systems.

Contribution

It provides the first comprehensive analysis of state-of-the-art digital watermarking and steganography methods tailored for ICAO-compliant facial images, assessing their effectiveness and limitations.

Findings

Digital watermarking can enable persistent verification of face images.

Steganography techniques offer complementary security features.

Trade-offs exist between robustness, imperceptibility, and compliance constraints.

Abstract

ICAO-compliant facial images, initially designed for secure biometric passports, are increasingly becoming central to identity verification in a wide range of application contexts, including border control, digital travel credentials, and financial services. While their standardization enables global interoperability, it also facilitates practices such as morphing and deepfakes, which can be exploited for harmful purposes like identity theft and illegal sharing of identity documents. Traditional countermeasures like Presentation Attack Detection (PAD) are limited to real-time capture and offer no post-capture protection. This survey paper investigates digital watermarking and steganography as complementary solutions that embed tamper-evident signals directly into the image, enabling persistent verification without compromising ICAO compliance. We provide the first comprehensive analysis of state-of-the-art techniques to evaluate the potential and drawbacks of the underlying approaches concerning the applications involving ICAO-compliant images and their suitability under standard constraints. We highlight key trade-offs, offering guidance for secure deployment in real-world identity systems.