Patent ID: 7376245

Claim:
An automatic tracking method for a golf swing, comprising the following steps of: attaching colored marks to plural positions including any one place of a golfer, which is a measurement objective, and at least one necessary position on a golf club that the golfer uses, before the golfer initiates a swing; photographing a background image of a swing place in which a golfer is not photographed and a swing moving image from a scene at address of the golfer to the finish thereof with a camera as color images; not only storing the photographed background image into a computer, but also storing plural still images converted from the swing moving image into the computer; adopting, of the still images, a specific still image in which all the marks can be recognized as a reference image and storing reference color information and coordinate data for positional information of each mark manually or automatically in advance; setting, on a still image being considered, for each of the mark positions thereon, a search range, which is a region including the position of the predicted mark on a still image adjacent in chronological order to the still image being considered and a wait range which is a region larger than the search range, in consideration of a case where the marks would not be recognized in the search range and setting a color range of each mark that is an allowable range, in which colors can be regarded as the same as reference color information thereof; changing the search range of the still image being considered to the wait range thereof in a case where a mark is hidden and not recognized in the search range thereof; regarding a pixel, as a position of a mark, in a case where the absolute value of a difference between a color of the pixel in the still image being considered on which a differential processing has been conducted with the background image in the search range or the wait range and the reference color information falls within the color range and is the minimum of absolute values obtained from other pixels to conduct a color search and obtain coordinate data; and automatically tracking the marks moving during the swing.