Dynamic programming matching technique, which is commonly used for the voice recognition, has been adapted to the time line images obtained by the spark tracing method for the high-speed air flow. As the high voltage sparks between two electrodes trace the air flow very well, we can measure the two or three-dimensional air velocities, if we can quantify the displacement and the time interval between sparks. In order to capture the three-dimensional profiles of each spark, the authors have utilized two synchronized high-speed cameras at different viewing angles. Thus each spark is captured in a separate frame. With the dynamic programming matching technique, the characteristics of the two consecutive spark lines are correctly corresponded and thus the three-dimensional displacements between sparks are quantified. Presently, the flow field of a high-speed air jet was measured and thus the applicability of this technique has been proved.

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