Scenario-Based Query Processing for Video-Surveillance Archives

Cataloged from PDF version of article.Automated video surveillance has emerged as a trendy application domain in recent years, and accessing the semantic content of surveillance video has become a challenging research area. The results of a considerable amount of research dealing with automated access to video surveillance have appeared in the literature; however, significant semantic gaps in event models and content-based access to surveillance video remain. In this paper, we propose a scenario-based query-processing system for video surveillance archives. In our system, a scenario is specified as a sequence of event predicates that can be enriched with object-based low-level features and directional predicates. We introduce an inverted tracking scheme, which effectively tracks the moving objects and enables view-based addressing of the scene. Our query-processing system also supports inverse querying and view-based querying, for after-the-fact activity analysis. We propose a specific surveillance query language to express the supported query types in a scenario-based manner. We also present a visual query-specification interface devised to facilitate the query-specification process. We have conducted performance experiments to show that our query-processing technique has a high expressive power and satisfactory retrieval accuracy in video surveillance. (C) 2009 Elsevier Ltd. All rights reserved

A histogram-based approach for object-based query-by-shape-and-color in image and video databases

Cataloged from PDF version of article.Considering the fact that querying by low-level object features is essential in image and video data, an efficient approach for querying and retrieval by shape and color is proposed. The approach employs three specialized histograms, (i.e. distance, angle, and color histograms) to store feature-based information that is extracted from objects. The objects can be extracted from images or video frames. The proposed histogram-based approach is used as a component in the query-by-feature subsystem of a video database management system. The color and shape information is handled together to enrich the querying capabilities for content-based retrieval. The evaluation of the retrieval effectiveness and the robustness of the proposed approach is presented via performance experiments. (C) 2005 Elsevier Ltd All rights reserved

Multiprocessor task scheduling in multistage hyrid flowshops: a genetic algorithm approach

This paper considers multiprocessor task scheduling in a multistage hybrid flow-shop environment. The objective is to minimize the make-span, that is, the completion time of all the tasks in the last stage. This problem is of practical interest in the textile and process industries. A genetic algorithm (GA) is developed to solve the problem. The GA is tested against a lower bound from the literature as well as against heuristic rules on a test bed comprising 400 problems with up to 100 jobs, 10 stages, and with up to five processors on each stage. For small problems, solutions found by the GA are compared to optimal solutions, which are obtained by total enumeration. For larger problems, optimum solutions are estimated by a statistical prediction technique. Computational results show that the GA is both effective and efficient for the current problem. Test problems are provided in a web site at www.benchmark.ibu.edu.tr/mpt-h; fsp

A histogram-based approach for object-based query-by-shape-and-color in image and video databases

Considering the fact that querying by low-level object features is essential in image and video data, an efficient approach for querying and retrieval by shape and color is proposed. The approach employs three specialized histograms, (i.e. distance, angle, and color histograms) to store feature-based information that is extracted from objects. The objects can be extracted from images or video frames. The proposed histogram-based approach is used as a component in the query-by-feature subsystem of a video database management system. The color and shape information is handled together to enrich the querying capabilities for content-based retrieval. The evaluation of the retrieval effectiveness and the robustness of the proposed approach is presented via performance experiments. © 2005 Elsevier Ltd. All rights reserved

Analysis of the complex light field generated by a deflectable mirror array device

An exact analysis of the scalar coherent monochromatic light field produced by a deflectable mirror array device is presented. The three-dimensional light field is related to the tilt angles of the mirrors. The first Rayleigh-Sommerfeld diffraction formula is used to model the diffraction. The analysis is carried out based on the assumption that the mirrors can be tilted with continuously varying angles, so the field produced by a finite (discrete) set of possible tilt angles is included as a special case

Sınıf Öğretmeni Adaylarının Çocuk Eğitimine İlişkin Metaforik Algılarının Kontrol Yaklaşımları Yönünden İncelenmesi

Bu araştırmada, sınıf ouml%253Bğretmeni adaylarının ccedil%253Bocuk eğitimine ilişkin metaforik algılarının, ouml%253Bğretmen kontrol duuml%253Bzeylerine gouml%253Bre incelenmesi amaccedil%253Blanmıştır. Araştırmaya, Hacettepe Uuml%253Bniversitesi İlkouml%253Bğretim Bouml%253Bluuml%253Bmuuml%253B Sınıf Ouml%253Bğretmenliği Ana Bilim Dalı 4. sınıfta okuyan 86 ouml%253Bğretmen adayı katılmıştır. Veri toplama aracı olarak, ouml%253Bğretmen adaylarından Ccedil%253Bocuk eğitimihellip%253B.gibidir%252Fbenzer. Ccedil%253Buuml%253Bnkuuml%253Bhellip%253B ifadesini tamamlamaları istenmiştir. Veriler, nitel araştırma youml%253Bntemlerinden iccedil%253Berik analizi tekniği kullanılarak analiz edilmiş, yuuml%253Bzde ve frekans değerleri de belirtilmiştir. Katılımcılar, en ccedil%253Bok toprak, bitki, bitki yetiştirmek, hamur, makine, halı dokumak gibi mecazlar kullanmışlardır. Uuml%253Bretilen metaforlar, gerekccedil%253Beleri dikkate alınarak, duuml%253Bşuuml%253Bk, orta ve yuuml%253Bksek duuml%253Bzey ouml%253Bğretmen kontroluuml%253B şeklinde uuml%253Bccedil%253B kategoriye ayrılmıştır. Araştırmanın bulgularına gouml%253Bre, ouml%253Bğretmen adaylarının yuuml%253Bksek duuml%253Bzey ouml%253Bğretmen kontroluuml%253Bne sahip oldukları sonucuna varılmıştır

Synthesis of three-dimensional light fields with binary spatial light modulators

Computation of a binary spatial light modulator (SLM) pattern that generates a desired light field is a challenging quantization problem for which several algorithms have been proposed, mainly for far-field or Fourier plane reconstructions. We study this problem assuming that the desired light field is synthesized within a volumetric region in the non-far-field range after free space propagation from the SLM plane. We use Fresnel and Rayleigh-Sommerfeld scalar diffraction theories for propagation of light. We show that, when the desired field is confined to a sufficiently narrow region of space, the ideal gray-level complex-valued SLM pattern generating it becomes sufficiently low pass (oversampled) so it can be successfully halftoned into a binary SLM pattern by solving two decoupled real-valued constrained halftoning problems. Our simulation results indicate that, when the synthesis region is considered, the binary SLM is indistinguishable from a lower resolution full complex gray-level SLM. In our approach, free space propagation related computations are done only once at the beginning, and the rest of the computation time is spent on carrying out standard image halftoning. © 2011 Optical Society of America