Localized wavelet based computerized tomography
نویسندگان
چکیده
We develop an algorithm to reconstruct the wavelet coee-cients of an image from the Radon transform data. The proposed method uses the properties of wavelets to localize the Radon transform and can be used to reconstruct a local region of the cross section of a body, using almost completely local data which signiicantly reduces the amount of exposure and computations in X-ray tomography. For example, for a local region of radius 20 pixels in a 256256 image the proposed method can reduce the exposure to 12:5% of the conventional ltered backprojection method. Compared to the existing schemes 5], 6], which can only reduce to 40%.
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