Lattice vector quantization (LVQ) reduces coding complexity and computation due to its regular structure. A new multistage LVQ (MLVQ) using an adaptive subband thresholding technique is presented and applied to image compression. The technique concentrates on reducing the quantization error of the quantized vectors by “blowing out” the residual quantization errors with an LVQ scale factor. The ...

In this thesis, we investigate some adaptive wavelet approaches for a so-called nonparametric regression model with strongly dependent Gaussian residuals. At first, we discuss data adaptive wavelet estimation of a trend function. It turns out that under certain smoothing conditions on the trend function, the asymptotic rate of the mean integrated square error (MISE) of a trend estimator obtaine...

This paper presents an adaptive thresholding approach intended to increase the number of detected corners, while reducing the amount of those ones corresponding to noisy data. The proposed approach works by using the classical Harris corner detector algorithm and overcome the difficulty in finding a general threshold that work well for all the images in a given data set by proposing a novel ada...

With an increasing emphasis on security, automated personal identification using hand vein biometric feature is becoming a very active topic in both research and practical applications. The objective of this work is to present a biometric authentication system for high security physical access control based on hand vein pattern. Hand vein biometric is selected, as it is foolproof, offers higher...

In this paper, we present a comparison of two techniques for noise reduction on CT set of projections. We use for filtering the Pointwise Wiener filter and thresholding of the Wavelet coefficients. We use the Anscombe transformation for noise variance stabilization. The Pointwise Wiener filter was computed with an adaptive windowing scheme for the calculation of local estimates. For the thresho...