The Karhunen-Loève transform in computerized tomography (Q1063533)

Image coding and image reconstruction from projections have been two major research issues for the engineer and scientist in the past decade. Recently, the need to combine these problems to code the projections of computerized tomography (CT) has arisen. Coding for projected data in CT differs significantly from conventional coding in that we are not necessarily concerned with the accuracy of decoded projections but rather with the accuracy of the reconstructed image. To solve this problem, we investigate a new variant of the Karhunen-Loeve (KL) transform of projected data. The KL transform gives a bound for coding by transform methods. The new variant KL transform is to be equivalent to finding the reconstructed image and then applying the conventional KL transform to this image.