A New Approach to Adapt and Insert a Watermark in Colour Images

In this paper a new robust and secure watermarking algorithm devoted to colour image protection is proposed. Based on substitutive methods, it permits to embed an invisible watermark in any channel (RGB) of the colour image, especially in the green one. The HSB colour space is used to estimate the watermark strength in order to adapt the watermark to the characteristics of the host image. This technique eliminates the problem of the channel choice and improves the blind detection process. Many simulation results show the robustness, against several attacks, of the watermark, its imperceptibility and its efficiency compared to other ones.