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Noise Reduction in CT Lung Images

M. Babykala, K. Sivanandam

Abstract


Image denoising is an essential pre-requisite in Computed Tomography and most common modality in medical imaging. The significance of the denoising is mainly due to that the effectiveness of clinical diagnosis using CT image depends upon the quality of the image. In higher radiation dose, high-quality images are produced but it leads to and a lower dose leads to the increase in image noise and results in unsharp images. In this paper, CT image noise can be reduced by various filters such as Gaussian and Prewitt filter and anisotropic diffusion filter. The anisotropic diffusion scheme can effectively smooth noisy background, yet well preserve edge and fine details in the restored image. Finally the root mean square values for the two filters are calculated and then compared to check the CT image quality.

Keywords


Computed Tomography, Radiation Dose, Denoising Filters, Image Quality.

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