Image Restoration Method Based on Pre-Filtering for Cone-Beam Computed Tomography
For the problem of image quality degradation of cone-beam Computed Tomography (CBCT) based on flat panel detector (FPD), a constrained least squares iteration (CLSI) restoration method based on pre-filtering is proposed. Firstly, the original projected images are denoised with bilateral filtering algorithm. Then, the denoised projected images are restored with CLSI. Finally, the final restored images are obtained by adding the noise images, which got by subtracting the projected images before and after denoising, to the restored images. The experimental results show that the method well inhibits the noise amplification phenomenon in image restoration, and increases the edge sharpness and contrast-to-noise ratio (CNR) of the projected images and slice images. The CBCT image quality is significantly improved with this method.
H. Zhang et al., "Image Restoration Method Based on Pre-Filtering for Cone-Beam Computed Tomography", Applied Mechanics and Materials, Vols. 229-231, pp. 1858-1861, 2012