Some embodiments include acquisition of color Doppler data, and detection of one or more transitions of the color Doppler data, each of the one or more transitions being between a first area representing flow velocity in a first direction and a second area representing flow velocity not in the first direction. A normalized energy function across one or more of the one or more transitions is calculated, a configuration of flow areas within the color Doppler data is determined, and aliasing corrections for the color Doppler data are determined based on the normalized energy functions and the configuration of flow areas.