METHOD OF STREAK ARTIFACT SUPPRESSION IN SPARSE-VIEW CT IMAGE RECONSTRUCTION

摘要

PURPOSE: A streak artifact suppressing method in a low density photography phase CT image reconfiguration is provided to obtain a clear CT image, by photographing and calculating a projection image of an object from various angles by using X-ray. CONSTITUTION: A sonogram is obtained from a CT image(S110). A high-strength area of reconfigured image is calculated by using a back projection FBP(Filtered Back Projection)(S130). A sinogram data of the high-strength area is calculated by the calculation(S140). A compound image is generated based on a compression sensing CS(Compressed Sensing)(S180). A final image is generated as the compound image is used as an initial guess of the CT image(S190). [Reference numerals] (S110) Obtaining a sinogram g^Acq; (S120) Reconfiguring an image using FBP(f^FBP) from the sinogram g^Acq; (S130) Calculating a high-strength area f^Bone from the f^FBP; (S140) Calculating sinogram data g^Bone by projecting the high-strength area f^Bone; (S150) Excluding component caused by the high-strength area by deducting the sinogram data g^Bone from the sinogram g^Acq; (S160) Obtaining the deducted sinogram g^Soft; (S170) Reconfiguring soft tissue image f^Soft through compressed sensing CS, f^Soft=CS_TV(g^Soft, λ:0.005, λ_s:=0.99,k:=40. flnit:=0; (S180) Generating a compound image f^Sum by adding the high-strength area f^Bone and the soft tissue image, f^Soft, f^Sum=f^Bone-f^Soft; (S190) Generating a final image f^Final through compressed sensing CS of the sinogram g^Acq using the compound image f^Sum as an initial estimation value of a CT image