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991.
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Wavelet domain-based video noise reduction using temporal discrete cosine transform and hierarchically adapted thresholding 总被引:1,自引:0,他引:1
A novel spatio-temporal filter for video denoising, which operates entirely in the wavelet domain, is proposed. For effective noise reduction, the spatial and temporal redundancies that exist in the wavelet domain representation of a video signal are exploited. First, a 2D discrete wavelet transform is applied to the input noisy frames. This is followed by a discrete cosine transform (DCT), which is applied to the temporal subband coefficients to minimise the redundancy among the consecutive frames. The DCT transformed, noise-free coefficients in the different wavelet domain subbands for the original image sequence are modelled using a prior having a generalised Gaussian distribution. On the basis of this prior, filtering of the noisy wavelet coefficients in each subband is carried out using a new, low-complexity wavelet shrinkage method, which utilises the correlation that exists between subsequent resolution levels. Experimental results show that the proposed scheme outperforms several state-of-the-art spatio-temporal filters in terms of both the peak signal-to-noise ratio and the visual quality 相似文献
995.
Using spin-on glass (SOG) as an adhesive, an Si wafer with thermal oxide was successfully bonded to one with an RF-sputtered Si3N4 film. This ensures that SOG films are effective in bonding Si wafers to less reactive surfaces than Si or SiO2 such as silicon nitride. It was also found that the previously reported bonding procedure can be simplified by suppressing the spin-induced radial striations of the SOG films. 相似文献
996.
Radiolabeled milk proteins ([carbon-14] beta-lactoglobulin or [carbon-14] kappa-casein) were added to raw skim milk used to prepare concentrated humanized infant formula. Ultracentrifugation of the sterilized product allowed separation of three fractions: lipids and the proteins associated with them; free casein micelles and other dense particles; and the fluid phase. Distribution of radiolabeled tracer proteins or of protein measured by chemical methods among these three phases varied significantly with differences in processing conditions (time and temperature of sterilization) or amount of certain additives (potassium hydroxide or urea). In the range of 0 to 8 meq/L of potassium hydroxide added to the formula after homogenization but before sterilization, the lipid layer content of carbon-14 from [carbon-14] kappa-casein in the sterilized product decreased by 4.7% for each 1 meq/L of added potassium hydroxide. Lipid layer content of protein decreased by 2 g/L (of a total of 32 g/L) for each 1 meq/L potassium hydroxide. Such differences in the structure of the product, related to interactions of protein with lipid, protein, or calcium phosphate, may correlate with physical properties and stability of milk-based lipid-rich products. 相似文献
997.
998.
E. I. Andreev 《Journal of Engineering Physics and Thermophysics》1987,53(2):870-876
Using integral relations between the velocity and enthalpy of gas, we develop an engineering method for the calculation of the local and average parameters of media and the heat and mass flux without using the empirical data about contact instruments.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 53, No. 2, pp. 191–198, August, 1987. 相似文献
999.
Yu. E. Roginskaya I. D. Belova B. Sh. Galyamov 《Chemical and Petroleum Engineering》1991,27(10):590-594
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 10, pp. 27–29, October, 1991. 相似文献
1000.
I. V. Brusilovskii V. D. Vermel' V. V. Mitrofovich Yu. G. Moskovko 《Chemical and Petroleum Engineering》1992,28(3):159-161
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 3, pp. 8–9, March, 1992. 相似文献