Time-varying delay measurement of video capture-to-display components with application to visual servoing

• We analyse the delays introduced by the video grabbing and display devices.
• We address the continuous measure of such delays.
• We discuss the known methods for measuring the delays.
• A novel automatic measurement procedure is outlined and assessed.
• Measurements for different video grabbing configurations are provided.
• Continuous delay measure is applied to visual servoing.
• Experiments with a simulated robotic arm are presented.

In this paper, we analyse the delays introduced by the video grabbing and display components in typical video based systems, and address the problem of providing a frame-by-frame measure of such delays. We discuss the known methods for measuring the latency due to the video acquisition process, and propose a method for measurement of the time-varying delays of the capture-to-display components, which does not require a dedicated measurement system and can be embedded in the same video communication system under observation. The method is demonstrated in the context of an autonomous visual servoing task, in which a simulated robotic arm, controlled by a tracking system, is used to hit/grasp a moving object.