Multilevel Wavelet Decomposition Watermarking Techniques

The merging of computer and communication technologies offer substantial new opportunities for processing and distribution of digital media. Along with powerful software and new devices such as digital cameras, scanners and printers, duplication, distribution, creation and manipulation of images can be easily and cheaply done. The protection of ownership and the prevention of unauthorized tampering of images are becoming increasingly important concerns to multimedia content owners especially when he content is to be made available through the internet, which is unsecured. Digital watermarking is considered by many a potential solution to this problem. It is a process which embeds some characteristics data in a image in advance which later can be extracted that can be used for authentication or proof of ownership. This paper proposed a combination of spread spectrum encoding of the embedded message and wavelet transform-based invariants for digital image watermarking. Using the proposed method, we investigated the effect of using different values of transparency of the original image. The experimental results show that the imperceptibility and robustness are guaranteed using the proposed technique