Non-Stationary CT Image Noise Spectrum Analysis
نویسندگان
چکیده
We investigate the spatial dependency of noise characteristics in CT images. The perceived image quality depends on the noisegranularity. Especially in low-dose applications the noise granularity influences the diagnostic value. A model is presented, that provides two-dimensional, stationary noise realizations for arbitrary image pixel locations from which two-dimensional Noise Power Spectrum estimates can be computed. It fully incorporates the CT reconstruction process for (indirect) fan-beam reconstruction, the quarter offset of the detector channels and the detector noise characteristics. It can be used with simulated and measured data and allows for the assessment of spectral noise characteristics for arbitrary objects.
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تاریخ انتشار 2010