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The success of research on matrix completion is evident in a variety of real-world applications. Tensor completion, which is a high-order extension of matrix completion, has also generated a great deal of research interest in recent years. Given a tensor with incomplete entries, existing methods use either factorization or completion schemes to recover the missing parts. However, as the number of missing entries increases, factorization schemes may overfit the model because of incorrectly predefined ranks, while completion schemes may fail to interpret the model factors. In this paper, we introduce a novel concept: complete the missing entries and simultaneously capture the underlying model structure. To this end, we propose a method called simultaneous tensor decomposition and completion (STDC) that combines a rank minimization technique with Tucker model decomposition. Moreover, as the model structure is implicitly included in the Tucker model, we use factor priors, which are usually known a priori in real-world tensor objects, to characterize the underlying joint-manifold drawn from the model factors. By exploiting this auxiliary information, our method leverages two classic schemes and accurately estimates the model factors and missing entries. We conducted experiments to empirically verify the convergence of our algorithm on synthetic data and evaluate its effectiveness on various kinds of real-world data. The results demonstrate the efficacy of the proposed method and its potential usage in tensor-based applications. It also outperforms state-of-the-art methods on multilinear model analysis and visual data completion tasks. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a non-parametric maximum a posteriori MAP framework for tracking non-rigid video objects. We formulate the region tracking problem as a MAP probability problem and define the probabilistic models in terms of the distances between the intensity distribution of the object and that of its spatial- and temporal-neighborhood. Furthermore, in order to better model the complex intensity changes due to non-rigid movement, we propose to use a non-parametric method to approximate the likelihood and prior terms in the MAP problem. The proposed non-parametric estimation algorithm mostly relies on intensity features and requires no time-consuming motion estimation. Finally, we employ a contour evolution method in the MAP optimization step to iteratively track the object contour. The experimental results demonstrate that the proposed method achieves satisfactory results and outperforms the previous parametric method. [Copyright &y& Elsevier]

This paper aims to construct mosaics from video sequences with moving objects. We propose to explicitly eliminate moving objects from the background. When dealing with only the retained background, we can simplify the following global motion estimation and exclude moving objects from the video mosaic.The proposed method consists of three stages. First, we apply a hierarchical block-based technique to detect and eliminate the moving regions from the background, and in the meantime we estimate the initial guess of the global motion. Next, we employ a hierarchical feature-based technique on the retained background regions to refine and derive the precise global motion. Last, we refine the segmentation results obtained at the first stage and warp all the retained background regions with respect to a reference coordinate system and integrate them into a video mosaic. Many experimental results are shown to demonstrate the effectiveness of the proposed work. [Copyright &y& Elsevier]

Looks at the development of a multiresolution-based watermarking technique used to enclose digital watermarks into images, in image processing. In-depth look at the technique; Effectiveness of the technique; Decomposition of the multiresolution signal; Discussion on data distribution.

Presents information on a study which focused on a proposed image authentication technique by embedding digital watermarks into images. Description of the embedding methods; Information on the watermark extraction method; Experimental results; Issues regarding the proposed method; Conclusions.

Presents information on the proposed MPEG-based technique for embedding digital `watermarks' into digital video. Method used to hide secret information into the signals to discourage unauthorized copying or attest the origin of the media; Advantages of the proposed method; Discussion on the experimental results.

Proposes the application of wavelet transform as a tool for image mosaic. Application of wavelet transform; Combination of signals; Information content analysis of signals; Emergence of wavelet theory.

Describes a fast computation algorithm for the two-dimensional discrete cosine transform (2-D DCT). Capabilities of the algorithm; Complexity analysis of the post-addition stage.

The challenge of single-image dehazing mainly comes from double uncertainty of scene radiance and scene transmission. Most existing methods focus on restoring the visibility of hazy images and tend to derive a rough estimate of scene transmission. Unlike previous work, in this paper we advocate the significance of accurate transmission estimation and recast our problem as deriving the optimal transmission map directly from the haze model under two scene priors. We introduce theoretic and heuristic bounds of scene transmission to guide the optimum and show that the proposed theoretic bound happens to justify the well-known dark channel prior of haze-free images. With the constraints on the solution space, we then incorporate two scene priors, including locally consistent scene radiance and context-aware scene transmission, to formulate a constrained minimization problem and solve it by quadratic programming. The global optimality is guaranteed. Simulations on synthetic data set quantitatively verify the accuracy and show that the transmission map successfully captures fine-grained depth boundaries. Experimental results on color/gray-level images demonstrate that our method outperforms most state of the arts in terms of both accurate transmission maps and realistic haze-free images. [ABSTRACT FROM AUTHOR]