Patent ID: 8356049
Filing Date: 2013-01-15
Classification: G06F

Abstract:
1. A landmark search apparatus for retrieving landmarks around an object, comprising: a position obtaining unit configured to obtain a current position of the object; a first storage unit configured to store landmark information including a name of a landmark and position information of the landmark related to the name; an retrieving unit configured to configured to retrieve the landmark information from the first storage unit based on the obtained current position; a second storage unit configured to store the retrieved landmark information as retrieved landmark information; and a determining unit configured to determine whether the retrieved landmark information is valid based on: i) the current position of the object; ii) a previous position of the object at a time of storing the retrieved landmark information in the second storage unit; iii) a first distance between the previous position and a farthest landmark from the previous position in landmarks indicated by the landmark information stored in the second storage unit; and iv) a second distance between the previous position and a landmark which is N-th farthest from the previous position in the landmarks indicated by the landmark information stored in the second storage unit, N being a predetermined number, wherein the determining unit determines whether a moving distance of the object from the previous position to the current position is more than a half of the first distance minus the second distance to determine whether the retrieved landmark information is valid.