161,722 research outputs found

    3D inference and modelling for video retrieval

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    A new scheme is proposed for extracting planar surfaces from 2D image sequences. We firstly perform feature correspondence over two neighboring frames, followed by the estimation of disparity and depth maps, provided a calibrated camera. We then apply iterative Random Sample Consensus (RANSAC) plane fitting to the generated 3D points to find a dominant plane in a maximum likelihood estimation style. Object points on or off this dominant plane are determined by measuring their Euclidean distance to the plane. Experimental work shows that the proposed scheme leads to better plane fitting results than the classical RANSAC method

    Feature extraction for speech and music discrimination

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    Driven by the demand of information retrieval, video editing and human-computer interface, in this paper we propose a novel spectral feature for music and speech discrimination. This scheme attempts to simulate a biological model using the averaged cepstrum, where human perception tends to pick up the areas of large cepstral changes. The cepstrum data that is away from the mean value will be exponentially reduced in magnitude. We conduct experiments of music/speech discrimination by comparing the performance of the proposed feature with that of previously proposed features in classification. The dynamic time warping based classification verifies that the proposed feature has the best quality of music/speech classification in the test database

    Exact solution at integrable coupling of a model for the Josephson effect between small metallic grains

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    A model is introduced for two reduced BCS systems which are coupled through the transfer of Cooper pairs between the systems. The model may thus be used in the analysis of the Josephson effect arising from pair tunneling between two strongly coupled small metallic grains. At a particular coupling strength the model is integrable and explicit results are derived for the energy spectrum, conserved operators, integrals of motion, and wave function scalar products. It is also shown that form factors can be obtained for the calculation of correlation functions. Further, a connection with perturbed conformal field theory is made.Comment: 12 pages, latex, no figure

    Automatic human face detection for content-based image annotation

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    In this paper, an automatic human face detection approach using colour analysis is applied for content-based image annotation. In the face detection, the probable face region is detected by adaptive boosting algorithm, and then combined with a colour filtering classifier to enhance the accuracy in face detection. The initial experimental benchmark shows the proposed scheme can be efficiently applied for image annotation with higher fidelity

    Exact form factors for the Josephson tunneling current and relative particle number fluctuations in a model of two coupled Bose-Einstein condensates

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    Form factors are derived for a model describing the coherent Josephson tunneling between two coupled Bose-Einstein condensates. This is achieved by studying the exact solution of the model in the framework of the algebraic Bethe ansatz. In this approach the form factors are expressed through determinant representations which are functions of the roots of the Bethe ansatz equations.Comment: 11 pages, latex, no figures, final version to appear in Lett. Math. Phy