Performance Evaluation of watermarking Schemes to Decide Meaningful Number of Shares

With the growth in digital world, it is becoming more important to find a method to protect the security of digital media. An image watermarking model based on visual secret sharing (VSS) is proposed for protection of ownership. In the embedding phase, the watermark is first divided by VSS into two parts, a hiding watermark and a secret watermark. Then only the hiding watermark is embedded into the original image and the secret watermark is reserved for watermark extracting by the owner. In the extracting phase, the hiding watermark is extracted from the watermarked image first and then directly superimposed on the secret watermark to recover the watermark information. Digital watermarking has been proposed as a possible brick of such protection systems. However, application of watermarking for multimedia content protection in realistic scenarios poses several security issues. A digital watermarking technique is used to generate meaningful shares. The secret image shares are watermarked with different cover images and are transmitted. At the receiving side, the cover images are extracted from the shares and stacked one by one which reveals the secret image progressively. Digital watermarking using visual cryptography provides improved security for encrypting secret images.