M Sakalli - Academia.edu (original) (raw)

Papers by M Sakalli

TENCON '97 Brisbane - Australia. Proceedings of IEEE TENCON '97. IEEE Region 10 Annual Conference. Speech and Image Technologies for Computing and Telecommunications (Cat. No.97CH36162)

A new model based compression scheme of face images is proposed as a combination of context-based... more A new model based compression scheme of face images is proposed as a combination of context-based and classic compression schemes. Deformable templates are employed to locate salient features of face images whose residuals are refined in a further residual vector quantization. Normalized face images are decomposed into subbands by using bi-orthogonal spline filters. Subbands and their first degree residuals are

2006 International Conference on Image Processing, 2006

ABSTRACT In this paper we consider the problem of faded wireless im- age and video transmission s... more ABSTRACT In this paper we consider the problem of faded wireless im- age and video transmission schemes under energy transmis- sion constraints. An example of such a constrained system experiencing Rayleigh fading is Code Division Multiple Ac- cess (CDMA) where power control is used. We imposed on the average energy transmitted per an image or image se- quence. A computationally

emo.org.tr

... M.Tolga SAKALLI *, Ercan BULUŞ *, Ion TUTANESCU ** *Computer Engineering Department, Trakya U... more ... M.Tolga SAKALLI *, Ercan BULUŞ *, Ion TUTANESCU ** *Computer Engineering Department, Trakya University, Turkey **Electronics Department, University of Pitesti ... If the comfort noise feature is used to improve voice quality, net bandwidth consumption averaged over a 20-30 ...

Optical Engineering, 1998

A method is developed for feature-based coding of human face images. Deformable templates, wavele... more A method is developed for feature-based coding of human face images. Deformable templates, wavelet decomposition, and residual vector quantization form three consecutive stages of the proposed method, which aims for recognition-based very low bit rate coding. Deformable templates are employed in localization of facial features and biorthogonal spline filters are used for the decomposition of segmented and normalized face images.

IEEE Transactions on Image Processing, 2006

A different contour search algorithm is presented in this paper that provides a faster convergenc... more A different contour search algorithm is presented in this paper that provides a faster convergence to the object contours than both the greedy snake algorithm (GSA) and the fast greedy snake (FGSA) algorithm. This new algorithm performs the search in an alternate skipping way between the even and odd nodes (snaxels) of a snake with different step sizes such that the snake moves to a likely local minimum in a twisting way. The alternative step sizes are adjusted so that the snake is less likely to be trapped at a pseudo-local minimum. The iteration process is based on a coarse-to-fine approach to improve the convergence. The proposed algorithm is compared with the FGSA algorithm that employs two alternating search patterns without altering the search step size. The algorithm is also applied in conjunction with the subband decomposition to extract face profiles in a hierarchical way.

Computer Vision and Image Understanding, 1999

This paper proposes a compression scheme for face profile images based on three stages, modelling... more This paper proposes a compression scheme for face profile images based on three stages, modelling, transformation, and the partially predictive classified vector quantization (CVQ) stage. The modelling stage employs deformable templates in the localisation of salient ...

Signal, Image and Video Processing, 2019

An approximated empirical mode decomposition generates a set of approximated intrinsic mode funct... more An approximated empirical mode decomposition generates a set of approximated intrinsic mode functions via a linear, nonadaptive but iterative approach. The decomposition was found to be very useful for a content-independent pattern recognition application. As the process is characterized by a system kernel matrix and performed iteratively, the approximated intrinsic mode functions can be understood as the original signals processed by a set of mask operations. Here, some properties of the decomposition are studied and an optimal design of the system kernel matrix is proposed. It is found that there is only one approximated intrinsic mode function if the exact perfect reconstruction condition is satisfied. Obviously, the approximated intrinsic mode function is the original signal. Therefore, the decomposition is practically not meaningful. To address this issue, the infinite number of iterations in the algorithm is truncated to a finite number of iterations. Also, the design of the system kernel matrix is formulated as an optimization problem. In particular, the exact perfect reconstruction error between the sum of the approximated intrinsic mode functions and the original signal is minimized and the total absolute sum of the difference between any two different eigenvalues of the iterative matrix is maximized subject to a stability condition. Here, the stability condition refers to the eigenvalues of the iterative matrix being between zero and one. Since the optimization problem is nonsmooth and nonconvex, a genetic algorithm is employed for finding its near global optimal solution. Compared to the conventional approximated empirical mode decomposition, computer numerical simulations show that our proposed approach can achieve more than one approximated intrinsic mode function with each approximated intrinsic mode function corresponding to an output of a more meaningful mask operation.

Pattern Recognition, 1999

This paper presents a model-based approach to locate head and face boundaries in a head-shoulder ... more This paper presents a model-based approach to locate head and face boundaries in a head-shoulder image with plain background. Three models are constructed for the images, where the head boundary is divided into left/right subboundaries and the face boundary is divided into left/right and top/bottom sub-boundaries. The left/right head boundaries are located from two thresholded images and the "nal result is the combination of them. After the head boundary is located, the four face sub-boundaries are located from the grey edge image. The algorithm is carried out iteratively by detecting low-level edges and then organizing/verifying them using high-level knowledge of the general shape of a head. The experimental results using a database of 300 images show that this approach is promising.

2006 40th Annual Conference on Information Sciences and Systems, 2006

2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2014

This paper presents a segmentation methodology of abdominal axial CT images. The aim of the study... more This paper presents a segmentation methodology of abdominal axial CT images. The aim of the study is to determine the location of mesenteric area from the axial images so the organs enclosed within can be localized precisely for diagnostic purposes. The challenge confronted here is that there is no a certain deterministic shape of abdominal organs. The methodology implemented here utilizes a curvelets stage followed by morphological image processing to achieve a contour emphasized segmentation from the gestalts of surrounding organs. This paper gives a detailed analysis of approach taken with the problems faced and a brief comparison wrt to other wavelet approaches.

The convergence speed of snakes is increased with the switching step size of local minima search ... more The convergence speed of snakes is increased with the switching step size of local minima search and they are incorporated with the local gradient information in the wavelet domain to provide extra speed of convergence to their final contours. This is important in model based compression applications using wavelet decomposition. The directional gradient information is extracted from the subbands provided

Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1990

International Conference on Pattern Recognition, 1998

This paper describes a multi-stage compression scheme of human face images. Snakes are employed i... more This paper describes a multi-stage compression scheme of human face images. Snakes are employed in localisation of facial features and biorthogonal spline filters are used for the decomposition of segmented and normalised face images. Wavelet coefficients are vector quantized in different number of cascaded stages depending on their contribution to the subjective quality of the image

Neural Networks, 1999. IJCNN'99. …, 1999

Page 1. A Fuzzy-Bayesian Approach to Image Expansion Mustafa SM , Hong Yan and Alan M. N. Fu Scho... more Page 1. A Fuzzy-Bayesian Approach to Image Expansion Mustafa SM , Hong Yan and Alan M. N. Fu School of Electrical and Information Engineering University of Sydney, NSW 2006, Australia Abstract This paper presents a ...