Cryptography meets watermarking: Detecting watermarks with minimal or zero knowledge disclosure

Digital watermarking schemes embed additional information into digital data and are used in various applications, such as proof of ownership or fingerprinting. For such applications, the presence of watermarks must be provable to any possibly dishonest party. Standard watermark detection requires knowledge of sensitive information like the watermark or the embedding key. This is a major security risk, since this information is in most cases sufficient to remove the watermark. Zero-knowledge watermark detection is a promising approach to overcome security issues residing around the process of watermark detection: cryptographic techniques are used to prove that a watermark is detectable in certain data, without jeopardizing the watermark. This paper gives an overview over such schemes and discusses their properties.