Revolution in digital multimedia has posted a number of problems related to the ownership of the multimedia & its authentication. The need for copy right protection has given an opportunity for the evolution of watermarking techniques. Digital watermarking is usually used as a tool or as a system which embeds the owner information on to the multimedia content such that whenever there is a dispute, the ownership can be determined. Primarily it is used for content protection, content authentication, content management and temper detection. In this paper we present detailed survey of existing audio watermarking techniques based on the different domains in which secret data is embedded along with the perceptual quality measures, applications and requirements. Future objectives are also discussed.

http://www.aicit.org/jdcta/ppl/JDCTA_July-38.pdf

Audio Watermarking: Current State of Art and Future Objectives

Multiview video consists of multiple views of the same scene. They require enormous amount of data to achieve high image quality, which makes it indispensable to compress multiview video. Therefore, data compression is a major issue for multiviews. In this paper, we explore an efficient fractal video codec to compress multiviews. The proposed scheme first compresses a view-dependent geometry of the base view using fractal video encoder with homogeneous region condition. With the extended fractional pel motion estimation algorithm and fast disparity estimation algorithm, it then generates prediction images of other views. The prediction image uses the image-based rendering techniques based on the decoded video. And the residual signals are obtained by the prediction image and the original image. Finally, it encodes residual signals by the fractal video encoder. The idea is also to exploit the statistical dependencies from both temporal and interview reference pictures for motion compensated prediction. Experimental results show that the proposed algorithm is consistently better than JMVC8.5, with 62.25% bit rate decrease and 0.37 dB PSNR increase based on the Bjontegaard metric, and the total encoding time (TET) of the proposed algorithm is reduced by 92%.

/pdf/an-efficient-fractal-video-sequences-codec-with-multiviews-3vqqn307dx.pdf

An Efficient Fractal Video Sequences Codec with Multiviews

This paper presents a method that jointly performs stereo matching and inter-view interpolation to obtain the depth map and virtual view image. A novel view synthesis method based on depth map layers representation of the stereo image pairs is proposed. The main idea of this approach is to separate the depth map into several layers of depth based on the disparity distance of the corresponding points. The novel view synthesis can be interpolated independently to each layer of depth by masking the particular depth layer. The final novel view synthesis obtained with the entire layers flattens into a single layer. Since the image view synthesis is performed in separate layers, the extracted new virtual object can be superimposed onto another 3D scene. The method is useful for free viewpoint video application with a small number of camera configurations. Based on the experimental results, it shows that the algorithm could improve the efficiency of finding the depth map and to synthesis the new virtual view images.

Novel view synthesis based on depth map layers representation

The increasing number of problems related to the ownership protection of the multimedia content & its authentication due to digital revolution had lead to evolution of digital watermarking techniques. Digital watermarking provides a viable solution in minimizing this problem and boosting the confidence among multimedia content i.e. text, image, video, audio providers to make available there content on a public domain. But the watermarks used in most of the watermarking methods are not personalized or unique because of which the problem of ambiguity arises if same watermark is used by two individuals. In this paper we propose a novel method to generate a unique personalized watermark which can act as authenticating information for any watermarking algorithm specially targeting an audio. The watermarks are generated through feature vectors extracted from the speech of an individual which are unique for a particular person. The uniqueness of the watermark is shown through exhaustive experiments.

/pdf/a-novel-approach-to-generate-watermarks-using-auditory-2bxd6k1nqp.pdf

A novel approach to generate watermarks using auditory features for audio

Virtual view rendering is one of the key techniques of interactive 3D video systems, and is analogue expression to the real world in virtual reality systems. This paper proposes a new algorithm of virtual view rendering between two views taken in the same scene at the same time, which is based on self-adaptive block matching disparity estimation. This algorithm outputs any view between the two origin views. In order to gain accurate dense disparity field, a method of self-adaptive block matching is proposed in disparity estimation according to the information of texture and gray scale. Image interpolation is used to render certain virtual view and reverse mapping is adopted to fill up holes formed in interpolation. Satisfying visual effect is shown in experimental result.

Virtual View Rendering Based on Self-adaptive Block Matching Disparity Estimation

A novel intermediate view synthesis method based on disparity estimation is presented in this paper. Color distance is adopted to set truncation value adaptively when Belief Propagation (BP) algorithm is used in disparity estimation. In view interpolation, the left and right part of the image are divided into three kinds using strong and weak consistency constraints separately. Then different strategy is applied according to the characteristic of each region. Experimental results show that it can synthesize virtual images with high quality.

A Novel Intermediate View Synthesis Method Based on Disparity Estimation

Digital watermarking is an efficient and promising approach to protect intellectual property rights of digital media. In this paper, a new scheme of robust audio watermarking based on Fractional Fourier transform (FRFT) domain for copyright protection is proposed, which utilizes the idea that FRFT can be considered as a rotation in time-frequency joint domain. Test results for imperceptibility of the watermark and its performance of detection are presented. The simulation study shows that the watermark performance is better than the classical spread spectrum audio watermarking scheme. Keywords-FRFT; audio watermark; spread-sectrum

Chong Wang

Papers

A Novel Intermediate View Synthesis Method Based on Disparity Estimation

A Scheme of Robust Audio Watermarking Based on FRFT for Copyright Protection