Adaptive speckle reduction with color transparency display [in medical US imaging]
We present an adaptive speckle reduction method and a display technique in medical ultrasonic imaging. The speckle reduction algorithm defines a reference histogram that is derived from a known speckle region. Smoothing is applied to each region based on the similarity of that region's histogram to the reference histogram. Regions of the original image are then classified into one of five categories: cyst, hypoechoic, mean speckle, hyperechoic, and edge; producing a color-coded, feature-segmented image. This feature-segmented image is then merged with the original image to produce a color transparency image. This final image preserves the detail of the original grayscale image while enhancing features extracted from the speckle reduced image.