19,277 research outputs found

    Parallel stereo vision algorithm

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    Integrating a stereo-photogrammetric robot head into a real-time system requires software solutions that rapidly resolve the stereo correspondence problem. The stereo-matcher presented in this paper uses therefore code parallelisation and was tested on three different processors with x87 and AVX. The results show that a 5mega pixels colour image can be matched in 5,55 seconds or as monochrome in 3,3 seconds

    Near real-time stereo vision system

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    The apparatus for a near real-time stereo vision system for use with a robotic vehicle is described. The system is comprised of two cameras mounted on three-axis rotation platforms, image-processing boards, a CPU, and specialized stereo vision algorithms. Bandpass-filtered image pyramids are computed, stereo matching is performed by least-squares correlation, and confidence ranges are estimated by means of Bayes' theorem. In particular, Laplacian image pyramids are built and disparity maps are produced from the 60 x 64 level of the pyramids at rates of up to 2 seconds per image pair. The first autonomous cross-country robotic traverses (of up to 100 meters) have been achieved using the stereo vision system of the present invention with all computing done onboard the vehicle. The overall approach disclosed herein provides a unifying paradigm for practical domain-independent stereo ranging

    Multi-view passive 3D face acquisition device

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    Approaches to acquisition of 3D facial data include laser scanners, structured light devices and (passive) stereo vision. The laser scanner and structured light methods allow accurate reconstruction of the 3D surface but strong light is projected on the faces of subjects. Passive stereo vision based approaches do not require strong light to be projected, however, it is hard to obtain comparable accuracy and robustness of the surface reconstruction. In this paper a passive multiple view approach using 5 cameras in a ’+’ configuration is proposed that significantly increases robustness and accuracy relative to traditional stereo vision approaches. The normalised cross correlations of all 5 views are combined using direct projection of points instead of the traditionally used rectified images. Also, errors caused by different perspective deformation of the surface in the different views are reduced by using an iterative reconstruction technique where the depth estimation of the previous iteration is used to warp the windows of the normalised cross correlation for the different views

    3D Face Recognition: Feature Extraction Based on Directional Signatures from Range Data and Disparity Maps

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    In this paper, the author presents a work on i) range data and ii) stereo-vision system based disparity map profiling that are used as signatures for 3D face recognition. The signatures capture the intensity variations along a line at sample points on a face in any particular direction. The directional signatures and some of their combinations are compared to study the variability in recognition performances. Two 3D face image datasets namely, a local student database captured with a stereo vision system and the FRGC v1 range dataset are used for performance evaluation

    Calibration and Sensitivity Analysis of a Stereo Vision-Based Driver Assistance System

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    Az http://intechweb.org/ alatti "Books" fĂŒl alatt kell rĂĄkeresni a "Stereo Vision" cĂ­mre Ă©s az 1. fejezetre

    Face Tracking dan Distance Estimation pada Realtime Video Menggunakan 3d Stereo Vision Camera

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    Face Tracking dan Distance Estimation pada realtime video menggunakan 3D stereo vision camera yang diajukan dalam paper ini adalah sebuah sistem deteksi wajah dan pengukuran estimasi jarak obyek wajah yang terdeteksi menggunakan 3D stereo vision camera. Dalam penelitian ini dikembangkan sistem untuk deteksi wajah menggunakan Haar Cascade Classifier dan untuk pengukuran estimasi jarak wajah dengan kamera menggunakan proyeksi gambar 2D menjadi 3D. Data 3 dimensi pada stereo vision kamera yang digunakan dapat direkonstruksi menggunakan proyeksi 2 Dimensi dari 2 buah titik kamera pada stereo vision camera. Implementasi deteksi wajah (face tracking) dan estimasi jarak pada realtime video menggunakan stereo vision camera yang diusulkan dapat bekerja untuk mendeteksi setiap obyek wajah manusia dengan baik, dan mampu memberikan estimasi jarak antara obyek wajah yang ditangkap dengan stereo vision camera secara riil. Deteksi wajah dan estimasi jarak wajah yang optimal adalah pada kisaran jarak 51-200cm, dengan deteksi wajah dan estimasi jarak yang ideal adalah pada posisi frontal view. Dari percobaan yang dilakukan dapat dihasilkan sebuah sistem tracking wajah yang robust dan dapat diketahui akurasi perhitungan estimasi jarak dibandingkan dengan jarak riil wajah mencapai 94.74 %

    Robust 3-Dimensional Object Recognition using Stereo Vision and Geometric Hashing

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    We propose a technique that combines geometric hashing with stereo vision. The idea is to use the robustness of geometric hashing to spurious data to overcome the correspondence problem, while the stereo vision setup enables direct model matching using the 3-D object models. Furthermore, because the matching technique relies on the relative positions of local features, we should be able to perform robust recognition even with partially occluded objects. We tested this approach with simple geometric objects using a corner point detector. We successfully recognized objects even in scenes where the objects were partially occluded by other objects. For complicated scenes, however, the limited set of model features and required amount of computing time, sometimes became a proble
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