Title :
Optimal subband wavelet thresholding using noisy and non-noisy data of images
Author :
Bekhtin, Yuri S.
Author_Institution :
Dept. of Autom. & Math. Modeling, Ryazan State Radioeng. Acad., Russia
Abstract :
Images in vision systems formed by microwave illumination are considered to be impaired by multiplicative noise. Nevertheless, there are both points corrupted by the noise and points with approximately correct values of intensity. Encoding of such images may apply a wavelet basis using thresholding of the wavelet coefficients. The optimal threshold was obtained for each subband of a multilevel wavelet transformation. It is iteratively reached by approaching the minimum distortion variance estimator, which holds the balance between errors added by distortion of non-noisy data and the residual noise of the de-noised data. Noisy and non-noisy data are found by applying the coefficient variance estimator
Keywords :
computer vision; image coding; iterative methods; microwave imaging; optimisation; parameter estimation; wavelet transforms; coefficient variance estimator; image coding; iterative method; microwave illumination; minimum distortion variance estimator; multilevel wavelet transformation; noisy data; non-noisy data; optimal subband wavelet thresholding; vision systems; wavelet basis; Image restoration; Lighting; Machine vision; Mean square error methods; Noise reduction; Rough surfaces; Smoothing methods; Speckle; Surface roughness; Wavelet coefficients;
Conference_Titel :
Image and Signal Processing and Analysis, 2001. ISPA 2001. Proceedings of the 2nd International Symposium on
Conference_Location :
Pula
Print_ISBN :
953-96769-4-0
DOI :
10.1109/ISPA.2001.938696
