Hello,

I want to develop an application (c# + mappoint2004 active x) in order to

- First define a route (this isn't a problem).. by clicking into map.ROUTE1

- Then I load a gps sentences retrieved by a car along the route.ROUTE2
(this isn't a problem)

But.. How I can discover differences between ROUTE1 and ROUTE2?
Are There any tips for matching two routes in order to check if the car drive along ROUTE1?

This is one of those things that is a lot easier with the human eye than with a computer.

The main problem in doing it with MapPoint is that you need the MapPoint-computed route coordinates. MapPoint will give you coordinates, but these are for viewing route segments - there's no guaranteee that they'll even be on the route!

You might be able to try grabbing an image and trying to compare the green route line with your GPS coordinates. Difficult but not impossible.


Richard

I need to match the route not only by human eyes but I need to obtain analytics information about routes differences..

I'm starting to improve this idea:

- Normalize ROUTE1 and ROUTE2 by using

foreach (MapPoint.Direction direction in route.Directions)
{
if (direction.Instruction.ToString().StartsWith("Part enza") ||
direction.Instruction.ToString().Contains("Svoltar e") ||
direction.Instruction.ToString().StartsWith("Arriv o"))
{ double lat = 0;
double lon = 0;
this.CalcPos(direction.Location, ref lat, ref lon); DAL.InsertLocationToDB(lat,lon,direction.Instructi on.ToString(),"DIRECTIONS");
}

}


- Then I match the NORMALIZED_ROUTE1 and NORMALIZED_ROUTE2
by watch the differences between each (lat,lon,direction.Instruction.ToString())

But the string matching algorithm (direction.Instruction ..) make me doubtful..

Another solution is matching the direction.location but this is a middle segment point.. Isn't impossibile to have start and end segment location?

p.s. Partenza(ita) == Start(eng)
Svoltare(ita) == turn(eng)
Arrivo(ita) == end(eng)

It isn't even a middle segment point - it is the middle view point (and altitude) for viewing that segment. This is what I was referring to erlier when I said that there was no guarantee that it is even on the segment!


Richard

>> There was no guarantee that it is even on the segment!

A point can be in another street?
If a point isn't on the segment (in the case isn't on another street) I Quantized it into a street.

Could be - it might even be over water.

Think of a case where the segment is a "U-shape". The point will be in the middle of the, and the road segmentwill go around it (down, below, and back up again)



Richard

I'm evalutating the image matching.

- I export a gif of mappoint route.
- I apply a filter in order to extract only the route
- then I discover the differences between route by perform a XOR betwen
IMAGE_ROUTE_A and IMAGE_ROUTE_B
- The XORED image is georeferencied: I can report the difference in mappoint

Is a good Idea?