Unwanted nonlinear gamma distortion frequently occurs in a great diversity of images during the procedures image acquisition, processing, and/or display. And often varies with capture setup change and luminance variation. Blind inverse correction, which automatically determines proper restoration value from given image, is paramount importance to attenuate distortion. For blind an adaptive tran...

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to make an accurate estimation of the uptake of radioactivity in an organ using the conjugate view method, corrections of physical factors, such as background activity, scatter, and attenuation are needed. the aim of this study was to evaluate the accuracy of four different methods for background correction in activity quantification of the heart in myocardial perfusion scans. the organ activit...

In this paper, we introduce a novel class of embedded exponential-type low-regularity integrators (ELRIs) for solving the KdV equation and establish their optimal convergence results under rough initial data. The schemes are explicit efficient to implement. By rigorous error analysis, first show that ELRI scheme provides order accuracy in $$H^\gamma $$ data $$H^{\gamma +1}$$ $$\gamma >\frac{1}{...

Abstract is NOT available

One of the most important challenges for practical face recognition systems is to make recognition more reliable under uncontrolled lighting conditions. We tackle this by using novel illumination-insensitive preprocessing method. The proposed face recognition system consists of a gamma correction, a preprocessing stage, a hybrid Fourier-based facial feature extraction, and Principal Component L...

We present a new uniformity correction (Fourier energy correction) which is designed to correct for gamma camera non-uniformity caused by variations of the energy response function within a wide spectral range. A convolution model is used to describe the spatial distortions of the energy response function. The model is solved in Fourier space. A preliminary flood acquisition is required to obta...