Video based Swimming Analysis for Fast Feedback

Abstract

<p>This paper proposes a digital camera based swimming analysis system for <br />athletic use with a low budget. The recreational usage is possible during the analysis phase, and no alterations of the pool environment are needed. The system <br />is of minimum complexity, has a real-time feedback mode, uses only underwater cameras, is flexible and <br />can be installed in many types of public swimming pools. <br />Possibly inaccurate camera placement poses no problem. Both commercially available and tailor made software were utilized for <br />video signal collection and computational analysis and for providing <br />a fast visual feedback for swimmers to improve the athletic performance.<br />The small number of cameras with a narrow overlapping view makes the conventional stereo calibration inaccurate and a direct planar calibration method is proposed in this paper instead. The calibration method is presented and its accuracy is evaluated. <br />The quick feedback is a key issue in improving the athletic <br />performance. We have developed two indicators, which are easy <br />to visualize. The first one is the swimming speed measured from <br />the video signal by tracking a marker band at the waist of the swimmer,<br />another one is the rudimentary swimming cycle analysis focusing<br />to the regularity of the cycle. <br /></p>