I am working on an iOS application which uses GTFS data. The data is provided by the local transit authority. When plotting the route overlays onto a map, I have found a number of outlying data points as seen in the image below:
*Sorry I didn't have enough reputation to post an image
In order to make the data more managable I have filtered the shape data through the Ramer-Douglas-Peucker Algorithm to remove redundant data points.
I am unsure of how to process the data further to remove these obviously incorrect points. Could someone offer some advice on to filter out these data points?
It looks like the agency has maybe added extraneous segments from the road to each stop's location on the side of the road? You might try filtering small segments that pop out to a stop location and back.
