AI-Powered Signature Biometrics : From Handwritten Signatures to Intelligent Identity Verification

This book was born from the gap between the old tradition of handwritten signatures and the new reality of digital identity. We are living through a strange time-AI makes forgeries easier than ever, but also gives us the best tools to detect them. The book argues we should not abandon the signature. We should make it smarter by embedding it with deep learning and explainable AI.The book moves step by step. Early chapters cover the basics: what makes a signature biometric, how signatures are captured and processed, and the classical methods that once defined the field. Then the book shifts into machine learning, deep learning, Siamese networks, and Transformers-the technologies that have revolutionized verification. Later chapters tackle forgery, adversarial attacks, and real-world deployment in banking, government, and border control. The final chapters look to the future: combining signatures with other biometrics, building explainable systems, and designing adaptive architectures that can learn and evolve.The book is meant for graduate students, industry practitioners, and policymakers. It draws on decades of research and the authors are grateful to the community that made this work possible. They hope readers will come to see the handwritten signature not as a relic, but as a human signal that-when paired with intelligent algorithms-can be strengthened and preserved for the security challenges ahead.