Advance Robust Watermarking Of Compressed and Encrypted Digital Media

Due to rapid increase of internet these days has raised the worth of digital media all over the world. Digital watermarking is an application associated with copyright protection. Any digital object can be used as a carrier to carry information. If the information is related to object then it is known as a watermark which can be visible or invisible. Robustness is checked well by extracting original watermark perfectly without any degradation in the original image. But while embedding watermark into a cover image, there is a possibility of degradation in quality of original image. In this work, we introduce a blind watermarking scheme based on DWT and SVD. For providing the security, Blowfish encryption algorithm is used. Due to great developments in use of internet, multimedia data can be easily copy and distributed without owners permission. Multimedia data includes images, audio and video. This poses a threat of unauthorized possession and usage of digital images. An additional threat is the illegal tampering and modification of digital images. Thus, the need arises for techniques to protect the copyright of digital material. Digital watermarking is one of the best solutions to avoid illegal copying, modifying and redistributing multimedia data. In digital watermarking watermark image is embedded into a cover image. By embedding watermark into the cover image the quality of cover image get degrade. This media data is often distributed in compressed and encrypted format and watermarking of these media data for copyright violation detection, proof of ownership, media authentication, sometimes need to be carried out in compressed-encrypted domain. Digital asset management is a system which handles data in compressed and encrypted format. A watermark should be embedded in such a way that it remains detectable as long as the perceptual quality of the digital content stays at an acceptable level