In this paper, we propose a simple and low complexity pulse peak detection algorithm using cascaded recursive digital filters and a slope sum function (SSF) with an adaptive thresholding scheme. The algorithm first eliminates noises in the photoplethysmogram (PPG) using the cascaded lowpass and highpass digital filters. The filters have been designed with 3-dB cutoff frequencies of 11 Hz and 0....

Palm lines include principal lines and wrinkles, which can uniquely describe an individual palmprint. On motive of palmprint image enhancement is to highlight palm lines. In this paper, a steerable filters based fuzzy unsharp masking algorithm is presented to enhance the contrast of a palmprint image. This method introduces the fuzzy set theory into the unsharp masking scheme. Moreover, in the ...

Auditory brainstem responses to clicks in quiet, notch noise, and highpass noise were recorded from 10 normal-hearing adults. Contrary to some reports, the latency of wave V increased as the center frequency of the notch decreased. Response identifiability and wave V amplitudes were similar for the notch and highpass noises. Thus, the additional frequencies below the notch did not contribute su...

Abstract Background The acoustic emission (AE) analysis has been used increasingly for gearbox diagnostics. Since AE signals are of non-linear, non-stationary and broadband nature, traditional signal processing techniques such as envelope spectrum must be carefully applied to avoid a wrong fault diagnosis. One technique that enhance the demodulation process vibration is empirical mode decomposi...

Surface multiresolution processing is an important subject in CAGD. It also poses many challenging problems including the design of multiresolution algorithms. Unlike images which are in general sampled on a regular square or hexagonal lattice, the meshes in surfaces processing could have an arbitrary topology, namely, they consist of not only regular vertices but also extraordinary vertices, w...

In this paper, a weighted order statistic (WOS) filtering structure admitting real-valued weights is introduced. The proposed filtering approach can effectively address a number of signal and image processing applications that require robust bandpass or highpass operations where the underlying contamination follows a nonsymmetric heavy-tailed distribution. The effect of negative weighting in th...

We propose a new class of mapping-based nonlinear quadratic Volterra filters for image enhancement. The input signal is mapped prior to filtering by a memoryless one-to-one nonlinear mapping function. The mapping function can be described by any arbitrary function and implemented by a simple look-up table. If necessary, an inverse mapping function is applied after filtering. Using this general ...