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Not defending grab, but osm has lots of false negatives. Satellite image does not have to be outdated - you can get less than 6 months old satellite image accur

Not defending grab, but osm has lots of false negatives. Satellite image does not have to be outdated - you can get less than 6 months old satellite image accurate enough to extract roads and buildings from Digital Globe or Airbus. Shameless plug: At tensorflight.com we have deep learning models that can do just that.

Krasnol 8y ago
I guess it depends on the sat image source which leads to costs. I'm sure you can use the newest/best data for your company because you can pass on the costs to your clients.
- kozikow 8y ago
  We indeed pass the cost of imagery to customers, but it's flexible. I.e. given the location and customer requirements we have a decision tree that picks the best image source from multiple providers based on freshness, spatial resolution, cost, and some other factors.
  - solarkraft 8y ago
    How does that tree approximately look? Which providers are there?
    - kozikow 8y ago
      > Which providers are there? In the "high spatial resolution" - i.e. 50 cm per pixel or less the well-known providers everyone is using are Digital Globe, Airbus or Nearmap. Above 50 cm it starts to get hard to confidently see enough detail. Google maps terms of service actually prohibits using satellite imagery for feature extraction ( https://cloud.google.com/maps-platform/terms/ https://cloud.google.com/maps-platform/terms/ ). Bing is the best on the cheap end. Actually, Bing donated imagery for OSM mapping purposes ( https://wiki.openstreetmap.org/wiki/Bing_Maps#Bing_Aerial_Imagery https://wiki.openstreetmap.org/wiki/Bing_Maps#Bing_Aerial_Im... ).
bzbarsky 8y ago
6 months old is outdated, depending on how fast things change on the ground. Even 2 months old can be outdated (e.g. can be missing houses built since, or showing houses that no longer exist). In some areas, this can be a very significant effect.
- kozikow 8y ago
  For most use cases it's more cost effective to use existing, slightly old imagery. On the other hand, for some use cases, it's necessary to get a very fresh image and commision an airplane flight (or drone if the area is very small) - e.g. hurricane damage mapping.
  - bzbarsky 8y ago
    It's more cost effective if your choices are to use the two vintages of imagery, sure. I understand why imagery can be stale. My point was that OSM data can be much more accurate than the imagery. Or not, depending on location.
- rmc 8y ago
  OpenStreetMap has a lot of things left to map. Sometimes, some correct data is better than no data.

Krasnol 8y ago

I guess it depends on the sat image source which leads to costs. I'm sure you can use the newest/best data for your company because you can pass on the costs to your clients.

kozikow 8y ago
We indeed pass the cost of imagery to customers, but it's flexible. I.e. given the location and customer requirements we have a decision tree that picks the best image source from multiple providers based on freshness, spatial resolution, cost, and some other factors.
- solarkraft 8y ago
  How does that tree approximately look? Which providers are there?
  - kozikow 8y ago
    > Which providers are there? In the "high spatial resolution" - i.e. 50 cm per pixel or less the well-known providers everyone is using are Digital Globe, Airbus or Nearmap. Above 50 cm it starts to get hard to confidently see enough detail. Google maps terms of service actually prohibits using satellite imagery for feature extraction ( https://cloud.google.com/maps-platform/terms/ https://cloud.google.com/maps-platform/terms/ ). Bing is the best on the cheap end. Actually, Bing donated imagery for OSM mapping purposes ( https://wiki.openstreetmap.org/wiki/Bing_Maps#Bing_Aerial_Imagery https://wiki.openstreetmap.org/wiki/Bing_Maps#Bing_Aerial_Im... ).

bzbarsky 8y ago

6 months old is outdated, depending on how fast things change on the ground. Even 2 months old can be outdated (e.g. can be missing houses built since, or showing houses that no longer exist). In some areas, this can be a very significant effect.

kozikow 8y ago
For most use cases it's more cost effective to use existing, slightly old imagery. On the other hand, for some use cases, it's necessary to get a very fresh image and commision an airplane flight (or drone if the area is very small) - e.g. hurricane damage mapping.
- bzbarsky 8y ago
  It's more cost effective if your choices are to use the two vintages of imagery, sure. I understand why imagery can be stale. My point was that OSM data can be much more accurate than the imagery. Or not, depending on location.
rmc 8y ago
OpenStreetMap has a lot of things left to map. Sometimes, some correct data is better than no data.