Interest point matching across arbitrary views

Bayram, İlker
Making a computer ءsee̕ is certainly one of the greatest challanges for today. Apart from possible applications, the solution may also shed light or at least give some idea on how, actually, the biological vision works. Many problems faced en route to successful algorithms require finding corresponding tokens in different views, which is termed the correspondence problem. For instance, given two images of the same scene from different views, if the camera positions and their internal parameters are known, it is possible to obtain the 3-Dimensional coordinates of a point in space, relative to the cameras, if the same point may be located in both images. Interestingly, the camera positions and internal parameters may be extracted solely from the images if a sufficient number of corresponding tokens can be found. In this sense, two subproblems, as the choice of the tokens and how to match these tokens, are examined. Due to the arbitrariness of the image pairs, invariant schemes for extracting and matching interest points, which were taken as the tokens to be matched, are utilised. In order to appreciate the ideas of the mentioned schemes, topics as scale-space, rotational and affine invariants are introduced. The geometry of the problem is briefly reviewed and the epipolar constraint is imposed using statistical outlier rejection methods. Despite the satisfactory matching performance of simple correlation-based matching schemes on small-baseline pairs, the simulation results show the improvements when the mentioned invariants are used on the cases for which they are strictly necessary.


System parameter adaptation based on image metrics for automatic target detection
Kürekli, Kenan; Akar, Gözde; Department of Electrical and Electronics Engineering (2004)
Automatic object detection is a challenging field which has been evolving over decades. The application areas span many domains such as robotics inspection, medical imaging, military targeting, and reconnaissance. Some of the most concentrated efforts in automatic object detection have been in the military domain, where most of the problems deal with automatic target detection and scene analysis in the outdoors using a variety of sensors. One of the critical problems in Automatic Target Detection (ATD) syst...
Simulation based investigation of an improvement for faster SIP re-registration
Tanrıverdi, Eda; Bilgen, Semih; Department of Electrical and Electronics Engineering (2004)
In this thesis, the Session Initiation Protocol (SIP) is studied and an improvement for faster re-registration is proposed. This proposal, namely the أregistration ا activationؤ, is investigated with a simulation prepared using OPNET. The literature about wireless mobile networks and SIP mobility is reviewed. Conditions for an effective mobile SIP network simulation are designed using message sequence charts. The testbed in [1] formed by Dutta et. al. that has been used to observe SIP handover performance i...
Chaotic digital modulation and demodulation
Öztürk, Uygar; Demirbaş, Kerim; Department of Electrical and Electronics Engineering (2005)
This thesis considers a communication system with chaotic modulation. Noise-like signals are generated by chaotic systems with different parameters to modulate binary digital signals. Demodulation is performed by both the Extended Kalman Filter (EKF) and Optimum Decoding Based Smoothing Algorithm (ODSA). Simulations are performed using both of these algorithms for different parameters affecting the performance of the communication system. Simulation results of these algorithms are compared.
Implementation of stanag 428 hf modem software on tms320c54x digital signal processor
Örümlü, Erhan; Baykal, Buyurman; Department of Electrical and Electronics Engineering (2004)
In this research, STANAG 4285 HF modem software is implemented on TMS320C54x fixed point digital signal processor. The software is optimized in order to meet real-time operation requirements. A fractionally spaced least mean square (LMS) decision feedback equalizer (DFE) is employed for the receiver. In order to improve the convergence of the LMS algorithm a multipass technique is utilized. Based on Watterson̕s model, an HF channel simulator is employed for evaluating the performance of the modem. The simul...
Implementing and evaluating the coordination layer andtime-synchronization of a new protocol for industrial communication networks
Turan, Ulaş; Schmidt, Şenan Ece; Department of Electrical and Electronics Engineering (2011)
Currently automation components of large-scale industrial systems are realized with distributed controller devices that use local sensor/actuator events and exchange shared events with communication networks. Fast paced improvement of Ethernet provoked its usage in industrial communication networks. The incompatibility of standard Ethernet protocol with the real-time requirements encouraged industry and academic researchers to provide a resolution for this problem. However, the existing solutions in the lit...
Citation Formats
İ. Bayram, “Interest point matching across arbitrary views,” M.S. - Master of Science, Middle East Technical University, 2004.