Patent ID: 8271228

Claim:
A trajectory information processing device comprising: an input receiving unit which receives input of coordinate information of points included in a continued trajectory by a user in the order in which the trajectory is drawn; a coordinate storage unit which, upon receipt of input of said coordinate information, stores the input coordinate information which was received in the order the input was received; a closed curve storage unit which stores closed curve information; a closed curve acquisition unit which repeatedly performs the following: when the coordinate information whose input was received is newly stored in said storage unit, said closed curve acquiring unit determines if one of the line segments that connects adjacently stored coordinate information other than the newly stored coordinate information from among the sequentially stored coordinate information, and a new line segment that connects the newly stored coordinate information and the coordinate information stored immediately before the newly stored coordinate information cross over each other and, if the new line segment crosses over the one of the line segments: (a) newly stores the closed curve information which specifies the current time as the time at which the closed curve was acquired in said closed curve storage unit; and (b) removes coordinate information stored prior to the newly stored coordinate information from said coordinate storage unit, and inserting the coordinate information of the point of the crossover immediately before the newly stored coordinate information so as to update said coordinate storage unit; and a vortex information outputting unit which, when closed curve information is newly stored in said closed curve storage unit, calculates the time interval between the time at which the closed curve specified in the newly stored closed curve information is acquired and the time at which the closed curve specified in the closed curve information stored immediately before said newly stored closed curve information is acquired, and outputs a numeric value associated in advance with the calculated time interval as parameter information specified by the user.