Method and apparatus for ultrasonic color flow imaging

A flow velocity processor for use in a color flow imaging system having reduced dynamic range requirements with an improved segmentation scan conversion on a pixel by pixel decision using velocity data derived from an autocorrelation vector after conversion to a unit vector, a compressed magnitude of the autocorrelation vector, and the two dimensional magnitude information. An autocorrelation vector processor generates autocorrelation vectors between pairs of N complex samples of at least one set of complex samples, each autocorrelation vector having amplitude and phase information. A unit vector convertor generates a corresponding unity amplitude autocorrelation vector for each processed input set of N complex samples, the phase of each unit amplitude autocorrelation vector being the same as the resultant autocorrelation vector, and the two components of the unit amplitude autocorrelation vector are used for subsequent calculation of the velocity and segmentation into a final color flow image. An autocorrelation vector magnitude information processing path may extract the amplitude component of each autocorrelation vector, generating compressed autocorrelation vector amplitude information for generation of a segmented image and a two dimensional image data processing path may extract two dimensional image data for the generation of a final segmented image. A scan convertor translates polar space data resampled rectangular space data and the two components of the unit vector are converted to a velocity value and, along with the compressed amplitude data and the two dimensional data, are ready for segmentation to generate the final display image.