Signal Processing Algorithms, Architectures, Arrangements, and Applications SPA 2009

In this paper, possibilities and restrictions of analog signal processing in the context of its application to neural networks are presented. Factors influencing the processing effectiveness are outlined. Current-mode as well as voltage mode techniques are considered. Both techniques possess advantages and disadvantages but the number of situations where the current-mode approach is superior over ... View full abstract»

Predictions for the properties of integrated circuits and systems fabricated in emerging nano-technologies indicate a rising level of static and dynamic faults due to new fault mechanisms. Not only transient faults due to particle radiation are becoming a problem, but also wear-out effects on transistors and interconnects. While transient faults can be covered by well-known technologies such as er... View full abstract»

In this paper we examine the scalability of several implementations of the 2-dimensional discrete cosine transformation in the context of image processing. By scaling down the quality of the transformation the required computational complexity also decreases. Using several benchmark images we can show that no significant loss of image quality results from downscaling the computational complexity b... View full abstract»

This article describes a new architecture for a parallel, digital image processor which performs several image processing tasks like segmentation, edge detection and noise removal. The architecture and algorithm modifications presented in this paper are aimed for reduction the FPGA area of a pixel, which represents basic image processing unit. The proposed modifications increase the functionality ... View full abstract»

One of the major part of any power converter is a control system. It must fulfil both requirements of power converter hardware topology and computing power necessary for control algorithm implementation. The development process of advanced control systems for power electronics is very time consuming and it must continuously follow on the technology progress. A flexible architecture of digital cont... View full abstract»

Design and optimization of a simple but efficient operational amplifier (OA) for switched-capacitor finite impulse response (SC FIR) filters are presented. The main design criteria are: proper characteristics for application in SC FIR filters, simplicity of the circuit structure, the area in the silicon realization and low power dissipation. The OAs have been realized in three different CMOS techn... View full abstract»

The progression from black & white to color television in the 1960's marked a significant development in TV technology. Since then the introduction of digital TV provided a major change for systems developers, less for consumer experience. The most current development under way in the TV and cinema arena is the progression towards 3-dimensional capture and consumption of video. This will provi... View full abstract»

CUDA (Compute Unified Device Architecture) is an efficient architecture developed by NVIDIA to compute parallel algorithms on Graphic Processing Unit (GPU). Using the API associated with this architecture, we develop fast parallel algorithms to compute standard methods for computerized tomography. Computation times are compared to their similar implementations on CPU to illustrate the efficiency o... View full abstract»

In this paper we propose efficient method for automatic estimation of intima and media boundary of common carotid artery (CCA) based on USG image analysis. The distance between intima and media is called intima-media thickness (IMT) and is used to predict cardiovascular events like myocardial infarction and stroke. At present, it is measured by manual segmentation of USG image by physician. Automa... View full abstract»

In the paper novel application of the level set method to heart .segmentation in ultrasound echocardiography is addressed. In the presented approach region of interest of the ultrasound image is calculated by means of Hough transform and speckle noise is reduced by anisotropic diffusion filter. The method is initially validated on USG-like simulated noisy images. View full abstract»

A short survey of scene depth estimation methods is presented. 3D reconstruction is a very complex problem and presents technical and computing challenges. This assessment is made in order to decide which method or a hybrid of methods can be utilized to build a system prototype for guiding blind pedestrians with special focus for the time-of-flight and stereovision. Main restrictions are pointed o... View full abstract»

In this paper a method for preparation a photographical picture with increased dynamic range from an initial digital picture in RAW format is presented. The algorithm is illustrated with examples using various formulas and mask dimensions. Then it is compared to the method based on the contrast reduction. View full abstract»

In this paper a novel approach to discrete signal filtering based on the Discrete Trigonometric Transforms (DTTs) is proposed. The concept is derived from the generalized convolution, modified by the rectangular windowing applied to the convolution matrix. The experimental results obtained for low-pass filters defined in domains of all 16 DTTs, as compared to the relevantly adjusted Finite Impulse... View full abstract»

Structural transformations are studied which facilitate finite-precision implementation of lifting-based quaternion multipliers. The idea is to substitute the original multiplier with that whose hypercomplex coefficient has permuted parts. The latter multiplier needs only simple pre- and postprocessing to play the role of the former, and the permutation can be selected so that the real coefficient... View full abstract»

This paper presents results from simulations of classic non-prefixed Wavelet-OFDM and its circular version called Circular Wavelet-OFDM using a cyclic prefix. Both modulators have been compared with standard OFDM multicarrier techniques in the high speed power line communication environment. Circular Wavelet-OFDM, as a hybrid modulation scheme lying between Wavelet-OFDM and OFDM, has all advantage... View full abstract»

The base problem in the watermark decoding process using coherent spectrum averaging method is output phase drift. The phase drift or jitter is undesired phenomenon in the output signal in the receiver's side of watermarking system. This phase drift is a result various stability of the quartz oscillators in the transmitter and receiver A/D converters. The laboratory results presented in this paper... View full abstract»

In the paper a novel open-loop solution of a sine wave sub sample time delay estimator operating in the discrete time domain is presented. The proposed solution is based on a concept of Hilbert transforming the reference-noised signal in order to estimate the phase difference relative to the received signal whose initial phase and delay are unknown. The engineered estimator works well around the n... View full abstract»

The contribution deals with a binary representation of real numbers. In domain of digital signal processing the number representation is either in fixed-point or floating-point form. There are many processors with fixed or floating-point representation and there are also several blocks used for arithmetical operations in FPGA using fixed or floating point. But generally these blocks do not have a ... View full abstract»

Summary form only given. The TANDEM project is a BMBF funded project with the goal to investigate several applications for wireless sensor networks i.e. in form of body area networks (BAN), automation networks, security networks etc. and develop a framework to construct such networks in a systematic and commercially feasible way. The approach of TANDEM to achieve these goals is to design a lego li... View full abstract»

A study of data pre-processing influence on accelerometer-based human activity recognition algorithms is presented. The frequency band used to filter-out the accelerometer signals and the number of accelerometers involved were considered in terms of their influence on the recognition accuracy. View full abstract»

In the paper a system for controlling a multimedia content viewer by hand gestures is presented. First, selected methods used for gesture recognition are described. Two different application cases of the system, i.e. for multimedia presentation purposes and for multimedia content viewing are outlined. Moreover, a proposal of improvement of the system combining these approaches is also given. The s... View full abstract»

In the paper a technique of eye tracking based on visible light is presented. The approach described does not require an additional hardware equipment used in the infrared eye tracking system. First, examples of existing eye tracking techniques were presented. Then, the proposed algorithm of image processing and the process of determining the eye position are described. The engineered eye tracking... View full abstract»