PNG image copyright protection and authentication using SVD hash and AES

There has been a rapid growth in the use of digital images due to development of modern technology. And easily available image editing tools and software´s have made these images easy to distribute, manipulate, and duplicate. All these reasons are enforcing a need for copyright enforcement methods that can provide copyright to the owner. In our proposed method a PNG image is used as the cover image in which the alpha-channel value of each pixel is set to default. That is, the cover image is a totally transparent color one at the beginning of the proposed data hiding process. When we apply data hiding technique to any PNG image which has transparency, it distorts the image transparency, which causes visibility issues with PNG image. To overcome this issue proposed technique uses 3 LSB of alpha channel to embed signals in image. In proposed technique owner encrypted information and hash code using SVD is embedded in image. SVD hash can be used to cross check the image contents. Experimental result show, there is no visible defect after embedding authentication signal into the cover images using proposed technique. In this paper, the proposed technique embeds the copyright information (authentication signal) which is encrypted using 128 bit AES and Singular Value Data (SVD) by using Shamir secret sharing data hiding technique. This technique is very robust and more secure as compared to previous data hiding techniques.