Watermark algorithm based on DWT for color image
Shen Jian-guo · Computer Engineering and Applications Journal · 2007
Robustness is one of the most basic requirements for invisible image watermark.Embedding strength and embedding location all affect robustness of watermark.In this paper,a new watermark algorithm for color images based on DWT is proposed.Making use of masking peculiarity of human visual system,the watermark image is self-adaptive embedded into the blocked lowest approximation components of blue components of color image on repeat embedding technology while most of other DWT methods embed watermark into the middle or high frequency components,so the embedding strength is great.Moreover,two extraction methods can be used to enhance cropping attack and need not origin host image while only one extraction method is used.Experimental results show that the proposed algorithm keeps the quality of the image well and is robust enough to JPEG compression、noise、filtering、image scaling、image enhancement、mosaic and cropping etc.