Feature based blind approach for robust watermarking

The central idea of this paper is to propose an innovative watermarking scheme for digital image authentication which withstands common image processing attacks. Some pixels are randomly selected from original image, so that all of them have a valid 3 × 3 neighborhoods. A binary sequence is constructed from those pixels by comparing them against average values of neighborhoods. The binary sequence is then converted into a watermark pattern in the form of a Hankel matrix to improve security of watermarking process and is then embedded within the host image. The operation of embedding and extraction of watermark is done in high frequency domain of Discrete Wavelet Transform since small modifications in this domain are not perceived by human eyes. This watermarking scheme deals with the extraction of the watermark information in the absence of original image, hence the blind scheme was obtained.