Apparatus and method for noise reduction of spectral computed tomography images and sinograms using a whitening transform

摘要

A method and apparatus is provided to denoise material-decomposition data generated using projection data from a spectral computed tomography scanner. A whitening transform is used to transform the material-decomposition data into uncorrelated components and perform denoising on the uncorrelated components. Using different denoising parameters for the various uncorrelated components, a flattening can be achieved for the standard deviation of the noise as a function of X-ray energy, which can be determined using mono-energetic images derived from the material-decomposition data. The whitening transformation and the denoising can be applied the material-decomposition sinograms and/or to material-decomposition images reconstructed from the material-decomposition sinograms.