WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7150

Browse

Filters

2004 - 200942010 - 20204

Settings

Author: search.filters.author.Gümüştekin, ŞevketLanguage: search.filters.language.tr

Search Results

Now showing 1 - 8 of 8
  • Conference Object
    Citation - WoS: 2
    Citation - Scopus: 5
    Ardışık Etkinleştirilen Çoklu Derinlik Kameraları Kullanımıyla 3b Nesne Geriçatımı
    (IEEE, 2020) Tunçer, Esra; Gümüştekin, Şevket
    Bu çalışmada, bir objenin 3-boyutlu yapısının tümüyle elde edilmesi amacıyla objenin çevresine 4 adet derinlik kamerası (Kinect v1) yerleştirilmiştir. Çoklu Kinect kullanımında karşılaşılan bilgisayar bant genişliği ve girişim problemleri eklenti USB 2.0 kontrolcüler ve elektronik kontrollü objektif kapakları ile çözülmüştür. Alınan görüntülerin birleştirilmesi için kalibrasyon işlemi kızılötesi görüntüler üzerinde uygulanmıştır. Eşleşme problemleri Döngülü En Yakın Nokta metoduyla giderilmiş ve %3.41 hata oranına sahip eşleşme elde edilmiştir. Farklı geometrik özelliklere sahip nesnelerin 3B modellenmesi için eşleştirilen nokta bulutlarına Meshlab yazılımı aracılığıyla Poisson Yüzey Geriçatımı işlemi uygulanmıştır
  • Conference Object
    Citation - WoS: 2
    Citation - Scopus: 4
    Tek Kamera ve Aynalar Kullanan Bir Görsel Denetleme Sistemi
    (Institute of Electrical and Electronics Engineers Inc., 2004) Gümüştekin, Şevket
    In this paper the geometrical properties of an imaging system are investigated. This system uses mirrors to simulate additional cameras. The geometry developed here helps us to capture the images of an object from meaningful viewpoint locations. The imaging system with the desired geometry is realized by adjusting the positions and orientations of mirrors. A special calibration pattern is used for the process of camera calibration which finds the unknown camera parameters and gives feedback about the degree of compliance with the desired geometry. The calibrated camera and its mirror images are used to create a 2D image of an object surface with a uniform geometry. After a pre-defined inner or outer surface of a test object is imaged from different view angles using mirrors, these images are warped and blended in a single image which is used for visual inspection. Hence, the vaguely defined process of inspecting 3D objects and their surface textures is converted to an efficient and well defined process of inspecting 2D images.
  • Conference Object
    Citation - Scopus: 1
    Hava Fotoğraflarından Deniz Kıyılarının Belirlenmesi
    (Institute of Electrical and Electronics Engineers Inc., 2006) Kahraman, Metin; Gümüştekin, Şevket
    The unique structures of different coastline segments provide distinctive image features for several applications such as oceanography, georeferencing, cartography and autonomous navigation. In this paper, a procedure involving automatic multiresolution coastline extraction is described. Using this method, sea and land textures are segmented utilizing cooccurrence and histogram features of wavelet image representation. The coastlines are identified as the boundaries of the sea regions.
  • Conference Object
    H264/avc ile Sıkıştırılmış Videoda Sahne Değişimi Kestirimi için Bir Yaklaşım
    (Institute of Electrical and Electronics Engineers Inc., 2007) Şimşek, Gökhan; Gümüştekin, Şevket
    In this paper, we provide methods to detect abrupt and gradual scene changes on ISO/ITU H264/AVC coded video sequence using macro-block type information. The analysis is realized in compressed domain without the need of full decompression to pixel domain. In order to realize the proposed methods, several video test sequences are constructed in QCIF resolution. The syntax and semantics, parsing, decoding processes of ISO/ITU H264/AVC is followed to realize such analysis and proposed methods are realized using reference software. The application addresses emerging standard ISO/ITU H264/AVC coded video databases as low level tools to realize a video summarization, abstraction or segmentation system.
  • Conference Object
    A Bayesian Approach for Licence Plate Recognition Developed on a Realistic Simulation Environment
    (Institute of Electrical and Electronics Engineers Inc., 2013) Efeler, Mahmut Cenk; Altınkaya, Mustafa Aziz; Gümüştekin, Şevket
    Template matching is one of the most common methods for license plate recognition. This method discards prior probabilities of license plate codes. The posterior code class probabilities constructed by including the prior probability information are expected to improve the recognition performance. The probability information that needs to be included requires extensive training data, which is quite costly to obtain. In order to generate these training images a license plate image simulator is developed with a realistic noise model. Simulated license plate images are then used to test a Bayesian decision theory based recognition procedure. Test results indicate that, with the inclusion of prior information, significant recognition gain is obtained with respect to standard template matching method at high noise levels.
  • Conference Object
    Citation - WoS: 2
    Citation - Scopus: 2
    Çok Bakışlı 3b Geriçatımın Polarizasyon Görüntüleme Kullanımıyla İyileştirilmesi
    (Institute of Electrical and Electronics Engineers Inc., 2014) Ozan, Şükrü; Gümüştekin, Şevket
    Performance of stereo imaging methods, which are used to find depth information of a scene, can be adversely affected by surface reflection properties of subjects in the scene and possible change in relative camera and light source positions. In this study a catadioptric multiview imaging system, which is constructed by using planar mirrors, is proposed. Stereo matching problems which are caused by the specular reflections in the scene are highlighted and it is shown that those problems can be significantly alleviated by using polarization images.
  • Conference Object
    Yapısal Aydınlatma Kullanarak Yüzeylerin Geometrik ve Yansıtıcılık Özelliklerinin Geri Çatımı
    (Institute of Electrical and Electronics Engineers Inc., 2015) Ozan, Şükrü; Gümüştekin, Şevket
    It is not possible to perform a robust and dense surface reconstruction for plain colored surfaces which have insufficient surface features, and for surfaces which have specularity effect because of the material nature by using traditional stereo imaging methods. The proposed surface scanner system in this work makes it possible to get a robust and dense surface reconstruction even for plain colored and/or semi glossy surfaces. Reflection properties of the surface material are also reconstructed to some extent by using the information gathered after scanning process. Moreover, the experimental results are shown.
  • Conference Object
    Modifiye Bitüm Görüntülerinde Gabor Öznitelikleri ile Doku Analizi
    (Institute of Electrical and Electronics Engineers Inc., 2008) Gümüştekin, Şevket; Topal, Ali; Şengöz, Burak
    İnşaat sanayinde, özellikle ulaşım uygulamalarının vazgerçilmez bir malzemesi olan bütün, gelişmekte olan malzeme teknolojilerinin de katkısı ile daha dayanıklı ve giivenilir yol ve yapıların yapılabilmesi için öncelikli bir araştırma konusu olmuştur. Çeşitli polimer katkı maddelerinin bitüme eklenmesi standart bir uygulama haline gelmiştir. Yapım sırasında kalite kontrolünün sağlanması ve denetlenmesi için modifiye bitümlerin test edilmesi büyük önem taşımaktadır. Bu çalışmada mekanik yöntemlere alternatif olan yeni bir yöntem sunulmuştur. Gabor öznitelikleri kullanılarak modifiye bitiim gorüntülerinin dokusal özellikleri incelenmiş; bitüme eklenen katkı maddelerinin ve bu maddelerin hangi oranda eklendiğinin algılanmasınzı büyük ölçüde mümkün olduğu gorülmüştür.