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

摘要

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_n) of the sequence: applying temporal filtering to the image (x_n) at instant n, the temporal filtering comprising fluoroscopic noise reduction processing; applying spatial filtering to the image (y_n) at instant n, the spatial filtering comprising: transforming the image (y_n) 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_n) 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_n) whose coefficients have been thresholded from the curvelet domain into the spatial domain using an inverse curvelet transform.