Bi-Orthogonal Wavelet Transform Based 3-D Image Watermarking on Colour Image

Watermarking technology is an effective approach to image content authentication and copyright protection, which has got notable achievements in recent years. Watermarking has been utilized by researchers for the security of digital documents. Due to the problems of data amount and color shifted, watermarking techniques on color image was not so widespread studied, although the color image is the principal part for multi-medium usages. In this paper we have proposed a method for watermarking color image on color image using Bi-Orthogonal Wavelet Transform. It consists of both a watermark stamping process which embeds a watermark in a source image, and a watermark extraction process which extracts a Watermark from a stamped image. As to the watermark image, pre-processing is applied first, in which the watermark image is decomposed by one level wavelet transformations. The experiment shows that the algorithm can guarantee the unperceivability and transparency of the digital image.