1. A method for providing a quantitative color flow display of moving matter using an ultrasound imaging system, the display being formed of pixels on a display device, which method comprises the steps of: transmitting acoustic beams to a region of interest in the body, which region of interest includes the moving matter; receiving echo beams from the region of interest; obtaining, at each portion of the region of interest, which portion is referred to as a pixel, a measure of velocity of moving matter in the pixel and a measure of direction of the velocity of the moving matter in the pixel; determining a maximum of the measure of velocity at each pixel in the region of interest over a predetermined period of time and the measure of direction of the maximum velocity; and displaying the measures of velocity of the pixels for the predetermined period of time wherein the measures of velocity and the measure of direction of the velocity are displayed using a color indicator which is relative to the maximum measure of velocity at each pixel and to the measure of direction of the maximum velocity.