Iterative reconstruction algorithm of projection data truncation problem caused by the long chords of pipe wall

作者：Liu Baodong^*; Zeng Li; Li Linsheng

来源：Chinese Journal of Scientific Instrument, 2011, 32(1): 52-56.

• Active contour model
• Computed Tomography
• Fast convergence speed
• Good stability
• High precision
• Iterative reconstruction algorithms
• Non destructive testing
• Piece-wise
• Piecewise constant
• Piecewise-constant correction
• Pipe walls
• Projection data
• Projection data truncation
• Reconstructed image
• Reconstruction algorithms
• Simultaneous algebraic reconstruction technique

Computed tomography (CT) can be used in nondestructive testing of pipe type objects. Truncation problem arises when the pipe wall is too thick and the energy of X-rays is not strong enough. Simultaneous algebraic reconstruction technique (SART) is suitable for dealing with common projection data truncation problem. However, when SART is used in dealing with the truncation problem caused by long chord of pipe, the reconstruction results still contain gray changing artifacts. In order to improve the quality of reconstructed image, piecewise-constant correction based on Chan-Vese (C-V) active contour model is introduced into SART and then the piecewise constant corrected SART (PCC-SART) reconstruction algorithm is obtained. Experimental results show that the proposed PCC-SART algorithm features a fast convergence speed, high precision and good stability.

• 出版日期2011