A method for reducing speckle artifact in an ultrasound image using a two-dimensional median filter having a diamond-shaped five-point kernel. The entire pixel image data is passed through the filter in a manner such that the center point of the kernel is effectively stepped down each range vector in...http://www.google.co.uk/patents/US5409007?utm_source=gb-gplus-sharePatent US5409007 - Filter to reduce speckle artifact in ultrasound imaging
