Secure Multi-level Green-Noise Diffused Watermarking with Printing Durability

Abstract

Digital watermarking by Green-Noise Diffusion Method has characteristics with visually high image quality, and print-resistance and reversibility, even embedded strongly. However, there are still some problems that the embedding capacity is not yet sufficient, and watermark is easily attacked as it is block type. Therefore, we obtained increased amount of embedding by multi-leveling, the extraction error is reduced by using both Gray code and error correction code, so that the printing durability is further improved, the watermark extraction from plain paper or dirty printed matter is enabled. And we obtained improved security from collusion attacks introducing the camouflage patterns. In the application as Annotation, it is possible to extract a stable watermark from various images by applying smoothing on the images.