Method for reducing noise in a sequence of fluoroscopic images by temporal and spatial filtering

Abstract

In the field of medical imaging using fluoroscopy, a method for reducing noise in a sequence of fluoroscopic images acquired by an X-ray detector comprises for each image (x) of the sequence: applying temporal filtering to the image (x) at instant n, the temporal filtering comprising fluoroscopic noise reduction processing; applying spatial filtering to the image (y) at instant n, the spatial filtering comprising: transforming the image (y) acquired at the instant n from the spatial domain into the curvelet domain using a curvelet transform, each transformed image being represented by a set of coefficients, thresholding the coefficients of the image (y) using a thresholding function, the thresholding function cancelling the coefficients below a third predetermined threshold, and preserving or adjusting the coefficients above the third predetermined threshold, transforming the image (Z) whose coefficients have been thresholded from the curvelet domain into the spatial domain using an inverse curvelet transform.