Motion compensated three dimensional wavelet transform based video compression and coding

Biçer, Aydın
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 spatially to their coarse and detail parts. The decomposition process utilizes both orthogonal and bi-orthogonal wavelet analysis filters. The transform coefficients are coded using an embedded image coding algorithm, called the أTwo-Dimensional Set Partitioning in Hierarchical Treesؤ (2-D SPIHT). Due to its nature, the 2-D SPIHT is applied to the individual subband frames. In the reconstruction phase, the 2-D SPIHT decoding algorithm and the wavelet synthesis filters are employed, respectively. The Peak Signal to Noise Ratios (PSNRs) are used as a quality measure of the reconstructed frames. The investigations reveal that among several factors, the multi-level (de)composition is the dominant one effective both on the signal compression and the PSNR level. The encoded videos compressed to the ratio of 1:9 are reconstructed with the PSNR of about 30 dB in the best cases.


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...
A comparative study on polygonal mesh simplification algorithms
Yirci, Murat; Ulusoy, İlkay; Department of Electrical and Electronics Engineering (2008)
Polygonal meshes are a common way of representing 3D surface models in many different areas of computer graphics and geometry processing. However, these models are becoming more and more complex which increases the cost of processing these models. In order to reduce this cost, mesh simplification algorithms are developed. Another important property of a polygonal mesh model is that whether it is regular or not. Regular meshes have many advantages over the irregular ones in terms of memory requirements, effi...
Graduate school of natural and applied sciences : electrical and electronic engineering
Aksay, Anıl; Akar, Gözde; Department of Electrical and Electronics Engineering (2010)
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 litt...
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 ...
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 ...
Citation Formats
A. Biçer, “Motion compensated three dimensional wavelet transform based video compression and coding,” M.S. - Master of Science, Middle East Technical University, 2005.