Hard EXIF: Protecting Image Authorship Through Metadata, Hardware, and Content

With the rapid proliferation of digital image content and advancements in image editing technologies, the protection of digital image authorship has become an increasingly important issue. Traditional methods for authorship protection include registering authorship through certification organization, utilizing image metadata such as Exchangeable Image File Format (EXIF) data, and employing watermarking techniques to prove ownership. In recent years, blockchain-based technologies have also been introduced to enhance authorship protection further. However, these approaches face challenges in balancing four key attributes: strong legal validity, high security, low cost, and high usability. Authorship registration is often cumbersome, EXIF metadata can be easily extracted and tampered with, watermarking techniques are vulnerable to various forms of attack, and blockchain technology is complex to implement and requires long-term maintenance. In response to these challenges, this paper introduces a new framework Hard EXIF, designed to balance these multiple attributes while delivering improved performance. The proposed method integrates metadata with physically unclonable functions (PUFs) for the first time, creating unique device fingerprints and embedding them into images using watermarking techniques. By leveraging the security and simplicity of hash functions and PUFs, this method enhances EXIF security while minimizing costs. Experimental results demonstrate that the Hard EXIF framework achieves an average peak signal-to-noise ratio (PSNR) of 42.89 dB, with a similarity of 99.46% between the original and watermarked images, and the extraction error rate is only 0.0017. These results show that the Hard EXIF framework balances legal validity, security, cost, and usability, promising authorship protection with great potential for wider application.