Method, apparatus, and system of matching a directed graph representation of a vehicle path to a road topology network in a digital map

An apparatus comprising:

• at least one processor;
• and
• at least one memory including computer program code for one or more programs,
• the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to:
• aggregate vehicle trajectory data into a vehicle path network, wherein the vehicle path network is a directed graph comprising a plurality of nodes;
• segment the vehicle path network into a plurality of linear features, wherein each linear feature of the plurality of linear features connects two nodes of the plurality of nodes in the vehicle path network;
• extend a geometry of at least one end of a feature of interest selected from among the plurality of linear features, wherein the geometry of the at least one end of the feature of interest is extended by selecting a longest linear feature connected to the at least one end;
• use a path-based map matcher to match the extended geometry to a map topology of a digital map to generate map matching results for the feature of interest;
• aggregate the map matching results of the feature of interest into an overall map matching result for the directed graph;
• and
• provide the overall map matching result as an output.

A non-transitory computer-readable storage medium, carrying one or more sequences of one or more instructions which, when executed by one or more processors, cause an apparatus to perform:

• aggregating vehicle trajectory data into a vehicle path network, wherein the vehicle path network is a directed graph comprising a plurality of nodes;
• segmenting the vehicle path network into a plurality of linear features, wherein each linear feature of the plurality of linear features connects two nodes of the plurality of nodes in the vehicle path network;
• using a path-based map matcher to separately match each linear feature to a map topology of a digital map to generate map matching results;
• selecting a feature of interest from among the plurality of linear features;
• extending a geometry of at least one end of the feature of interest, wherein the geometry of the at least one end of the feature of interest is extended by selecting a smoothest linear feature connected to the at least one end that has the least angle difference between the feature of interest;
• providing the extended geometry of the feature of interest as an input to the path-based map matcher to generate the map matching results for the feature of interest;
• aggregating the map matching results of each linear feature and the map matching results for the feature of interest into an overall map matching result for the directed graph;
• and
• providing the overall map matching result as an output.