Blind watermarking technique for greyscale image using DCT and 1-D Walsh coding

This paper presents a robust watermarking technique to copyright an image. Proposed technique is totally based on DCT and is different from most of the available techniques. Watermark is embedded block-wise into the image to protect the ownership against the ltering, cropping and noise attack. Before embedding the watermark we are converting it into Walsh coded watermark [1]. In proposed approach there will be a variation in gain factor two different host images. The experimental results show that the proposed approach ensures invisibility, security and robustness against signal processing.