WANG Bo-bo, LAI Zhong-xin, HUANG Lian-qing, WANG Xu-chao. MHMM-based computed radiography image-denoising method[J]. Editorial Office of Optics and Precision Engineering, 2002,(2): 188-193
WANG Bo-bo, LAI Zhong-xin, HUANG Lian-qing, WANG Xu-chao. MHMM-based computed radiography image-denoising method[J]. Editorial Office of Optics and Precision Engineering, 2002,(2): 188-193DOI:
a lot of noises will be brought into the system. Therefore
only by knowing their resources
characteristics and relationship with signals
can the authors smooth them. On the basis of analyzing the computed radiography system in detail
the authors point out that there are two kinds of noises affecting the quality of a computed radiography image: Gaussian white noise and Poisson noise. Firstly
the statistical characteristics of wavelet coefficients and Gaussian white noise are summarized. Then
they are described with the mixture Gaussian model and hidden Markov model (HMM)
which can fit the dependency of wavelet coefficients between scales. Finally
the novel algorithm developed by the authors is compared with other wavelet-based denoising methods.
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references
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