9,642 research outputs found

    A Robust Online Method for Face Recognition under Illumination Invariant Conditions

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    In case of incremental inputs to an online face recognition with illumination invariant face samples which maximize the class-separation criterion but also incorporates the asymmetrical property of training data distributions In this paper we alleviate this problem with an incremental learning algorithm to effectively adjust a boosted strong classifier with domain-partitioning weak hypotheses to online samples which adopts a novel approach to efficient estimation of training losses received from offline samples An illumination invariant face representation is obtained by extracting local binary pattern LBP features NIR images The Ada-boost procedure is used to learn a powerful face recognition engine based on the invariant representation We use Incremental linear discriminant analysis ILDA in case of sparse function for active near infrared NIR imaging system that is able to produce face images of good condition regardless of visible lights in the environment accuracy by changes in environmental illumination The experiments show convincing results of our incremental method on challenging face detection in extreme illumination

    Fast and Accurate Algorithm for Eye Localization for Gaze Tracking in Low Resolution Images

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    Iris centre localization in low-resolution visible images is a challenging problem in computer vision community due to noise, shadows, occlusions, pose variations, eye blinks, etc. This paper proposes an efficient method for determining iris centre in low-resolution images in the visible spectrum. Even low-cost consumer-grade webcams can be used for gaze tracking without any additional hardware. A two-stage algorithm is proposed for iris centre localization. The proposed method uses geometrical characteristics of the eye. In the first stage, a fast convolution based approach is used for obtaining the coarse location of iris centre (IC). The IC location is further refined in the second stage using boundary tracing and ellipse fitting. The algorithm has been evaluated in public databases like BioID, Gi4E and is found to outperform the state of the art methods.Comment: 12 pages, 10 figures, IET Computer Vision, 201

    On the Design and Analysis of Multiple View Descriptors

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    We propose an extension of popular descriptors based on gradient orientation histograms (HOG, computed in a single image) to multiple views. It hinges on interpreting HOG as a conditional density in the space of sampled images, where the effects of nuisance factors such as viewpoint and illumination are marginalized. However, such marginalization is performed with respect to a very coarse approximation of the underlying distribution. Our extension leverages on the fact that multiple views of the same scene allow separating intrinsic from nuisance variability, and thus afford better marginalization of the latter. The result is a descriptor that has the same complexity of single-view HOG, and can be compared in the same manner, but exploits multiple views to better trade off insensitivity to nuisance variability with specificity to intrinsic variability. We also introduce a novel multi-view wide-baseline matching dataset, consisting of a mixture of real and synthetic objects with ground truthed camera motion and dense three-dimensional geometry
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