Graduate school of natural and applied sciences : electrical and electronic engineering

Aksay, Anıl
In this thesis, a number of novel techniques for error resilient coding and streaming for multiview video are presented. First of all, a novel coding technique for stereoscopic video is proposed where additional coding gain is achieved by downsampling one of the views spatially or temporally based on the well-known theory that the human visual system can perceive high frequencies in 3D from the higher quality view. Stereoscopic videos can be coded at a rate upto 1.2 times that of monoscopic videos with little visual quality degradation with the proposed coding technique. Next, a systematic method for design and optimization of multi-threaded multi-view video encoding/decoding algorithms using multi-core processors is proposed. The proposed multi-core decoding architectures are compliant with the current international standards, and enable multi-threaded processing with negligible loss of encoding efficiency and minimum processing overhead. End-to-end 3D Streaming system over Internet using current standards is implemented. A heuristic methodology for modeling the end-toend rate-distortion characteristic of this system is suggested and the parameters of the system is optimally selected using this model. End-to-end 3D Broadcasting system over DVB-H using current standards is also implemented. Extensive testing is employed to show the importance and characteristics of several error resilient tools. Finally we modeled end-to-end RD characteristics to optimize the encoding and protection parameters.


Motion compensated three dimensional wavelet transform based video compression and coding
Biçer, Aydın; Ünver, Baki Zafer; Department of Electrical and Electronics Engineering (2005)
In this thesis, a low bit rate video coding system based on three-dimensional (3-D) wavelet coding is studied. In addition to the initial motivation to make use of the motion compensated wavelet based coding schemes, the other techniques that do not utilize the motion compensation in their coding procedures have also been considered on equal footing. The 3-D wavelet transform (WT) algorithm is based on the أgroup of framesؤ (GOF) concept. The group of eight frames are decomposed both temporally and spatiall...
Implementation of a distributed video codec
Işık, Cem Vedat; Akar, Gözde; Department of Electrical and Electronics Engineering (2008)
Current interframe video compression standards such as the MPEG4 and H.264, require a high-complexity encoder for predictive coding to exploit the similarities among successive video frames. This requirement is acceptable for cases where the video sequence to be transmitted is encoded once and decoded many times. However, some emerging applications such as video-based sensor networks, power-aware surveillance and mobile video communication systems require computational complexity to be shifted from encoder ...
Dynamic system modeling and state estimation for speech signal
Özbek, İbrahim Yücel; Demirekler, Mübeccel; Department of Electrical and Electronics Engineering (2010)
This thesis presents an all-inclusive framework on how the current formant tracking and audio (and/or visual)-to-articulatory inversion algorithms can be improved. The possible improvements are summarized as follows: The first part of the thesis investigates the problem of the formant frequency estimation when the number of formants to be estimated fixed or variable respectively. The fixed number of formant tracking method is based on the assumption that the number of formant frequencies is fixed along the ...
Computer simulation and implementation of a visual 3-d eye gaze tracker for autostreoscopic displays
İnce, Kutalmış Gökalp; Alatan, Abdullah Aydın; Department of Electrical and Electronics Engineering (2009)
In this thesis, a visual 3-D eye gaze tracker is designed and implemented to tested via computer simulations and on an experimental setup. Proposed tracker is designed to examine human perception on autostereoscopic displays when the viewer is 3m away from such displays. Two different methods are proposed for calibrating personal parameters and gaze estimation, namely line of gaze (LoG) and line of sight (LoS) solutions. 2-D and 3-D estimation performances of the proposed system are observed both using comp...
Software process improvement in a software development environment
Konuralp, Zeynep; Bilgen, Semih; Department of Electrical and Electronics Engineering (2007)
A software process improvement study is presented. The literature on software development processes and their improvement is reviewed. The current peer review process at Software Engineering Directorate of the X Company, Ankara, Türkiye (XCOM) is studied and the static software development metrics based on a recent proposal have been evaluated. The static software metrics based improvement suggestions and the author’s improvement suggestions discussed with the senior staff are compared. An improved peer rev...
Citation Formats
A. Aksay, “Graduate school of natural and applied sciences : electrical and electronic engineering,” Ph.D. - Doctoral Program, Middle East Technical University, 2010.