Patent ID: 8954265
Filing Date: 2015-02-10
Classification: G01C,G06F,G09B

Abstract:
1. A method of resolving a location from an ordered list of location reference points, each location reference point being representative of a node in a first digital map and each location reference point being associated with information relating to the properties of a specific line or segment in said first digital map emanating from or incident at the node, the method comprising the steps of: (i) for each location reference point, identifying at least one candidate node existing in a second digital map, and identifying at least one candidate line or segment existing in said second digital map emanating from or incident at said candidate node; (ii) performing a route search within said second digital map between: at least one of an identified candidate node and a corresponding identified candidate line or segment emanating therefrom or incident thereat, and at least one of an identified candidate node for the next location reference point appearing in the list and a corresponding identified candidate line or segment emanating therefrom or incident thereat, and extracting from said second digital map each line or segment forming part of the route so determined between said candidate nodes; and (iii) repeating step (ii) for each consecutive pair of location reference points up to and including the final location reference point appearing in the list, wherein, when more than one candidate node and/or more than one candidate line or segment in the second digital map is identified for a given location reference point, the method further comprises a step of identifying a most likely candidate node and/or a most likely candidate line or segment, and using the most likely candidate node and/or most likely candidate line or segment in the route search, wherein elevation information is associated with each location reference point, the elevation information relating to the location reference point and/or the specific line or segment emanating from or incident at the node in the first digital map represented by the location reference point, the elevation information comprising gradient information and a distance of validity for the gradient information along the candidate line or segment, and using the elevation information in said step of identifying the most likely candidate node and/or most likely candidate line or segment when more than one candidate node and/or candidate line or segment is found in the second digital map to resolve the location in the second digital map.