Distinctive Scale Invariant Image Watermarking using Hermite Splines

Abstract

This paper we present a robust non blind watermarking scheme. The proposed scheme embeds the watermark into the color image. This watermarking scheme based on a sample spline approach by extracting distinctive invariant features from images. It can be used to perform reliable matching between different views of an object. This paper also describes an approach for object recognition using these invariant features. The recognition can be performed by matching individual features to a database of known features of objects using a fast nearest neighbour algorithm.

In this paper we use the low frequency components of image blocks for data hiding to obtain high robustness against attacks. We take four samples of the approximation coefficients of the image blocks to construct a spline curve in the   2-D space. Here the slope of this spline curve is invariant to the gain factor, which is used for watermarking purpose. We embed the watermarking code by constructing a spline curve according to watermarking bits. We compute the distribution of the slope of the embedding spline curve for designing a maximum likelihood decoder.