Method of removing artifacts in an ecographic doppler video

A computer-implemented denoising method for removing artefacts from a doppler-type ultrasound video, comprising steps of:

• acquiring a plurality (n) of frames composing an ultrasound video;
• identifying for each of the n frames a first pixel category representative of first pixels of an n-th frame containing ultrasound signal;
• and a second pixel category representative of second pixels of an n-th frame containing doppler activation;
• generating for each frame belonging to the plurality of frames, a first set of image data in order to associate to each pixel position of the corresponding frame at least a first or a second category so as to categorize the pixels of the corresponding frame and identifying for each frame the pixels containing doppler activation;
• generating at least a persistence sequence associated to a frame portion containing identification data ordered according to a frame sequence such that adjacent identification data in the frame sequence refers to consecutive frames, wherein each identification data assumes a first value if the corresponding frame portion contains doppler activated pixels or a second value different from the first value if the corresponding frame portion does not contain doppler activated pixels;
• in the persistence sequence associated with the frame portion, calculating a length of each persistence sub-sequence comprising consecutive identification data having the first value;
• calculating a reference threshold based on length distribution of the persistence sub-sequences referring to whole identification data for the n frames;
• identifying for each of the n frames a second set of image data (SEED) in order to associate to each pixel position in the corresponding frame:
• wherein the information that the pixel position belongs to the second category when the frame n corresponds to one of the persistence sub-sequences having a length greater than the threshold so as to be representative of a pixel with real doppler signal;
• or
• the information that the pixel position belongs to the first category when the frame n corresponds to another one of the persistence sub-sequences having a length shorter than the threshold so as to be representative of an artefact;
• and
• removing from the corresponding frame a pixel at the pixel position identified as being representative of the artifact.