Transforming a geometric algorithm into an effective computer program is a difficult task. This transformation is particularly made hard by the basic assumptions of most theoretical geometric algorithms concerning complexity measures and (more crucially) the handling of robustness issues, namely issues related to arithmetic precision and degenerate input. The paper starts with a discussion of t...

Digital watermarking is one of commonly used solutions for copyright protection. A watermark should be imperceptible and robust to various attacks. In this paper, we address watermarking for motion data. Our watermarking scheme is based on two well-known ideas, so called multiresolution representation and spread spectrum. We embed a watermark into a motion signal by perturbing large detail coef...

Object tracking is an important research direction in computer vision and is widely used in video surveillance, security monitoring, video analysis and other fields. Conventional tracking algorithms perform poorly in specific scenes, such as a target with fast motion and occlusion. The candidate samples may lose the true target due to its fast motion. Moreover, the appearance of the target may ...

In this paper, the regularized estimation of the displacement vector field (DVF) of a dynamic image sequence is considered. A new class of non-quadratic convex regularization functionals is employed to estimate the motion field in the presence of motion discontinuities and occlusions. The derivation of the functionals is based on entropy considerations and do not require parameter tuning as in ...

Magnetic Resonance Imaging allows for minimally invasive targeting and thermal ablation of tumors while monitoring the temperature distribution. Conventional MR thermometry procedures are hampered by either low accuracy or high sensitivity to motion artifacts due to the use of a reference temperature image. A new, dual-echo technique has been developed to obtain the temperature distribution wit...

This paper describes a new approach to the problem of estimating motion in video image sequences. The algorithm operates on the complex coeecients obtained by applying the new Complex Discrete Wavelet Transform to each frame. This transform implements an eecient analysis by an ensemble of Gabor-like lters of diierent orientation and scales. The Gabor-like form of the lters means that local tran...

In this paper, we propose a robust motion segmentation method based on the matrix factorization and subspace separation. We, first, mathematically prove that the shape interaction matrix can be derived using QR decomposition rather than Singular Value Decomposition(SVD). Using shape interaction matrix, we solve the motion segmentation problem using spectral graph clustering technique. We exploi...

A new model selection criterion based on physical characteristics of underlying motion models is proposed. The proposed criterion is then incorporated in a robust motion segmentation scheme, which is based upon robust least K-th order statistical model fitting. The proposed model criterion has been compared with many other competing techniques and it’s shown to be more suitable for the motion s...

In this paper, we propose a robust watermarking scheme called Double-Layer Spread-Transform Dither Modulation (DL-STDM) for watermarking motion data. We embed watermarks into the DCT domain of the quaternion logarithm image (QLI) representation of motion data. Experimental results demonstrate that our scheme is more robust than existing motion watermarking schemes against a wide variety of atta...

In this paper we propose a method for estimating the motion parameters for a rotating camera with a possibly changing focal length. This method is suitable for analysing sport event videos. The estimation process consists of three stages: (1) robust estimation of the 2-D translational components, (2) 2-D block-based motion estimation and (3) robust estimation of a parametric motion model. For m...