Method for HDR-like imaging using industrial digital cameras

Dynamic range of the scene can be significantly wider than the dynamic range of an image because of limitations of A/D conversion. In such a situation, numerous details of the scene cannot be adequately shown on the image. Standard industrial digital cameras are equipped with an auto-exposure function that automatically sets both the aperture value and cameras exposure time. When measuring a scene with atypical distribution of light and dark elements, the indicated auto-exposure time may not be optimal. The aim of work was to improve, with minimal cost, the performance of standard industrial digital cameras. We propose a low complexity method for creating HDR-like image using three images captured with different exposure times. The proposed method consists of three algorithms: (1) algorithm for estimating whether the auto-exposure time is optimal, (2) algorithm which determines exposure times for two additional images (one with shorter and another with longer than auto-exposure time), and (3) algorithm for HDR-like imaging based on fusion of three previously obtained images. Method is implemented on FPGA inserted into standard industrial digital camera. Results show that the proposed approach produces high quality HDR-like scene-mapped 8-bit images with minimal computational cost. All improvements may be noticed through the performance evaluation.

     

Automatic heart sound detection in pediatric patients without electrocardiogram reference via pseudo-affine Wigner–Ville distribution and Haar wavelet lifting

Having in mind the availability of electronic stethoscopes, phonocardiograms (PCGs) have become popular for cardiovascular functionality monitoring and signal processing applications. Detection of fundamental heart sounds (HSs), S1s and S2s, is considered to be a crucial step in PCG analysis. Electrocardiogram (ECG), noted as a reference signal, is often synchronously recorded in order to simplify the S1/S2 detection process. Nevertheless, electronic stethoscopes are frequently used without additional ECG equipment. We propose a new algorithm for automatic fundamental HSs detection via: joint time-frequency representation based on pseudo affine Wigner–Ville distribution (PAWVD), Haar wavelet lifting scheme (Haar-LS), normalized average Shannon energy (NASE) and autocorrelation. The performance of the proposed algorithm was calculated on both normal (50) and pathological (75) PCG recordings, eight seconds long each, contributed by 125 different pediatric patients. The algorithm showed relatively high recall (90.41%) and precision (96.39%) rates of S1/S2 detection procedure in a variety of PCG signals, without ECG as a reference. Furthermore, it indicated the ability to overcome splitting within the S1/S2 heart sounds.     

A class of non-canonic,driving-point immittance realizations of passive,common-ground,transformerless, two-element-kind RLC networks

A new class of non-canonic, driving-point immittance realizations of passive, common-ground, transformerless, two-element-kind RLC networks with minimum number of nodes is presented. Six new algorithms of realization are developed by application of canonic, orthogonal matrix transformations with reduced number of degrees of freedom. the number of applied RLC elements of one kind can be minimized and of the other kind reduced, while their parameter values are calculated directly in a linear way.     

Neural network based cell scheduling in ATM node

This letter deals with the queueing discipline for the superposition of arrival processes in the asynchronous transfer mode (ATM) case, particularly for the bursty traffic. A competitive algorithm, based on neural networks, for the cell scheduling is suggested. Computer simulations demonstrate that the new algorithm may be very useful in the bursty traffic case: the cell loss rate is at least one order of magnitude lower than in case of the classical round-robin discipline     

Global Communications Newsletter January 2010

Includes: ITU and Ministerial Seminar on Switchover from Analog to Digital Terrestrial Television Broadcasting in Central and Eastern Europe (Belgrade, Serbia); Is It Time for Specialized Telecommunication Engineering Education in the United States?; IEEE ComSoc Beijing Chapter Newsletter; FuturICT 2009 - The First Hungarian-Japanese Joint Conference on Future Information and Communication Technologies     

Transmission-line theory approach to solution of state equationsfor linear-lumped circuits

Linear-lumped circuits containing capacitors and/or inductors are described by differential equations. In computer-aided circuit analysis, these equations are discretized in time, thus being reduced to approximate formulas involving samples of voltages and currents. It is shown that these relations can be interpreted as exact equations for networks containing transmission lines. Hence, some features of the approximate formulas gain a clear physical interpretation. In particular, convergence and energy balance properties of the formulas become obvious, confirming advantages of the trapezoidal rule over all other formulas     

Frequency-dependent OP-AMP gain influence on parameters of the single amplifier biquad filters

The influence of the finite gain and gain-bandwidth product of the operational amplifier on the parameters of the active RC filter has been investigated in the present paper. Single amplifier biquad filters were analysed for the case when the central frequency in the pole pair does not depend on the amplifier gain, i.e. when S = 0. The general results were obtained for such filters, describing well the filter behaviour at low as well as at high frequencies. On the basis of the results obtained, the deviation of the realized parameters from the desired values can be determined, and thereby the necessary correction of the filter calculation can be made. The experimental results agree well with the theoretical ones.     

Copy-move forgery detection based on multifractals

Multimedia Tools and Applications - Digital images and video are the basic media for communication nowadays. They are used as authenticated proofs or corroboratory evidence in different areas like:...