Record number :
395835
Title of article :
Tomographic reconstruction and estimation based on multiscale natural-pixel bases
Author/Authors :
Bhatia، نويسنده , , M.، نويسنده , , Karl، نويسنده , , W.C.، نويسنده , , Willsky، نويسنده , , A.S.، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 1997
Pages :
16
From page :
463
To page :
478
Abstract :
We use a natural pixel-type representation of an object, originally developed for incomplete data tomography problems, to construct nearly orthonormal multiscale basis functions. The nearly orthonormal behavior of the multiscale basis functions results in a system matrix, relating the input (the object coefficients) and the output (the projection data), which is extremely sparse. In addition, the coarsest scale elements of this matrix capture any ill conditioning in the system matrix arising from the geometry of the imaging system. We exploit this feature to partition the system matrix by scales and obtain a reconstruction procedure that requires inversion of only a well-conditioned and sparse matrix. This enables us to formulate a tomographic reconstruction technique from incomplete data wherein the object is reconstructed at multiple scales or resolutions. In case of noisy projection data we extend our multiscale reconstruction technique to explicitly account for noise by calculating maximum a posteriori probability (MAP) multiscale reconstruction estimates based on a certain self-similar prior on the multiscale object coefficients. The framework for multiscale reconstruction presented here can find application in regularization of imaging problems where the projection data are incomplete, irregular, and noisy, and in object feature recognition directly from projection data.
Journal title :
IEEE TRANSACTIONS ON IMAGE PROCESSING
Serial Year :
1997
Link To Document :
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