Questions about/best practices to capture for map data creation (signs and points)

Community
1

I am really impressed at the ability of Mapillary to create signs and other point features. I have a bunch of questions and hope you all on the forum can help.

  1. Is it normal for map data (signs and points) to be generated randomly and very slowly? I have some captures a couple of weeks old with no points produced (example). Then I have more recent captures with a patchwork of points.

  2. I have noticed that the GPS tracks from my X5 are stored with 10 points per second. However, when they come into Mapillary, there is 1 point per second. This seems to lead to fewer photos published and I wonder if this is compromising creation of map data like signs and points? In the photo below the blue line is my track, the black dots are the .gpx provided with the video upload, and the green line is someone else’s track.

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There seems to be no information about units of time less than a second in the data. Does this mean it is a feature request to Insta360? Is there a way Mapillary could just guess at the times to enable more points to come in? Do other GPS loggers output files with more resolution? It just seems like a waste to capture at 30fps but end up with 1fps!

5

Hi @henryu ,

  1. Yes, we are improving point creation to be faster and more consistent, there are some known issues there today that we are improving upon. cc: @balys

  2. Mapillary generally tries to sample video to be 1 frame every 3 meters - this provides a good experience as you navigate the imagery as well. So its not dependent on frames per second, but frames per meter (0.33 frames per meter). In general this should be sufficient for creating map data. You’re right that other GPS loggers can output files with more detailed resolution, but generally we do not need 30 fps for the Mapillary use case, so what you are doing should already be sufficient.

6

@boris Thanks for the reply. This graphic might better explain why I am curious (sorry it is hard to read). The dots in the image are my .gpx track (10 per second). The green dots are of course what Mapillary mapped. In this area, the distance between GPS points is about 2.4 meters but the distance between the Mapillary points are about 24 meters = 0.04 frames per meter.

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7

Oh - that seems like a bug - could you send me a link to the Mapillary.com capture and maybe also the source file you uploaded? (Was it images or video?

8

The source is video from the Insta360 X5.

Link to sequence: Mapillary

Link to video and gpx from Insta360 receiver: For Boris