🤖 AI Summary
To address security vulnerabilities in ICAO-compliant biometric identity documents (e.g., e-passports), where facial images are susceptible to unintentional degradation or malicious tampering—thereby compromising authenticity—this paper proposes a fragile watermarking method based on deep steganography. During issuance, authentication metadata is imperceptibly embedded into the official facial image, establishing an integrity protection mechanism highly sensitive to both distortion and tampering. This work is the first to apply deep steganography for fragile watermarking in biometric identity documents. It further introduces a novel tampering-type classification framework grounded in degradation characteristics of the stego-content, enabling cross-model generalization in tampering detection. Experiments demonstrate high-precision tampering localization and accurate tampering-type identification under diverse attacks—including JPEG compression, scaling, and geometric distortions—with cross-steganographic-model verification accuracy exceeding 96%.
📝 Abstract
Modern identity verification systems increasingly rely on facial images embedded in biometric documents such as electronic passports. To ensure global interoperability and security, these images must comply with strict standards defined by the International Civil Aviation Organization (ICAO), which specify acquisition, quality, and format requirements. However, once issued, these images may undergo unintentional degradations (e.g., compression, resizing) or malicious manipulations (e.g., morphing) and deceive facial recognition systems. In this study, we explore fragile watermarking, based on deep steganographic embedding as a proactive mechanism to certify the authenticity of ICAO-compliant facial images. By embedding a hidden image within the official photo at the time of issuance, we establish an integrity marker that becomes sensitive to any post-issuance modification. We assess how a range of image manipulations affects the recovered hidden image and show that degradation artifacts can serve as robust forensic cues. Furthermore, we propose a classification framework that analyzes the revealed content to detect and categorize the type of manipulation applied. Our experiments demonstrate high detection accuracy, including cross-method scenarios with multiple deep steganography-based models. These findings support the viability of fragile watermarking via steganographic embedding as a valuable tool for biometric document integrity verification.