Flow is represented by a synthesized or artificial pattern. Motion is visualized by apparent displacement of pixels from one frame to the next. An artificial pattern is introduced in order to present the flow. A changing parameter, such as velocity, is viewed as a function of multiple images or over time. The rate of change of the parameter is proportional to the perceived or actual motion. Humans perceive flow as a live stream, such as tap water pouring from a faucet or a stream in a creek. Flow associated with medical imaging is presented in a similar way, such that a pattern or other flow information persists over multiple images. The flow is synthesized by generating patterns and moving the generated patterns in the field of view. The direction and rate of motion of the pattern are a function of the direction and rate of the flow.