No abstract

Abstract-Digital watermarking plays a very important role in copyright protection. It is one of the techniques which are used for safeguarding the origins of the image, audio and video by protecting it against Piracy. This paper proposes a low variance based spread spectrum watermarking for image and video in which the watermark is obtained twice in the receiver. The watermark to be added is a binary image of comparatively smaller size than the Cover Image. Cover Image is divided into number of 8x8 blocks and transform into frequency domain using Discrete Cosine Transform. A gold sequence is added as well as subtracted in each block for each watermark bit. In most cases, researchers has generally used algorithms for extracting single watermark and also it is seen that finding the location of the distorted bit of the watermark due to some attacks is one of the most challenging task. However, in this paper the same watermark is embedded as well as extracted twice with gold code without much distortion of the image and comparing these two watermarks will help in finding the distorted bit. Another feature is that as this algorithm is based on embedding of watermark in low variance region, therefore proper extraction of the watermark is obtained at a lesser modulating factor. The proposed algorithm is very much useful in applications like realtime broad casting, image and video authentication and secure camera system. The experimental results show that the watermarking technique is robust against various attacks.

The paper introduces a Digital Image Watermarking technique based on Transform domain. The purpose of doing the watermarking in transform domain is to give more robustness in the watermarking process looking into its fast real time implementation and also the computational complexity which comes often in the implementation process. In the proposed algorithm, a binary watermark is embedded in a grayscale image(cover image). The cover image is segregated into blocks of high and low variances. The cover image is transformed into frequency domain and comparative higher variance blocks are considered for embedding the binary watermark. Integer portion of the transformed DC coefficients of the considered blocks undergoes binary conversion and binary bits of watermark are embedded in those co-efficients. Both Walsh Transform and Walsh Hadamard transform are used for frequency domain conversion of the image and to make a comparative study as well. Software simulation of the algorithm is done using MATLAB

Abstract. The main objective of our work is to align multiple sequences together on the basis of statistical approach in lieu of heuristics approach. Here we are proposing a novel idea for aligning multiple sequences in which we will be considering the DNA sequences as lines not as strings where each character represents a point in the line. DNA sequences are aligned in such a way that maximum overlap can occur between them, so that we get maximum matching of characters which will be treated as our seeds of the alignment. The proposed algorithm will first find the seeds in the aligning sequences and then it will grow the alignment on the basis of statistical approach of curve fitting using standard deviation.