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Quality of aerial imagery

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I often find bad placed OSM objects because of bad background imagery used as a reference.

Of course, finding reliable OSM reference objects (ie: official imports) helps to re-align backgound. But, if they are not available, how to assess image alignment, orthorectification (and optionally flight date)?

Is there a common place where we can find such information?

asked 29 Apr '21, 09:07

Cascafico's gravatar image

Cascafico
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accept rate: 0%


One Answer:

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Hi Cascafico, it depends on the editor you’re using. JOSM offers you a range of 7 or more views, but even they differ in view. I always survey and take some ways or crossings as references to check the alignment with a GPS, surveying is the best way to improve OSM to be a better image or map with greater and more details. If you re using areal views, there is only one option check them to find the best fit. But if you can’t find any sufficient image to control, just leave it as is and wait for later accurate data.

answered 29 Apr '21, 10:32

Hendrikklaas's gravatar image

Hendrikklaas
9.3k207238387
accept rate: 5%

Thanks Hendrik. JOSM has a nice feature to retrieve image info by right clicking on backgouund image, but I couldn't never get anything. I'm aware that imagery is released for free as-it-is, but unfortunately there are situations like this airstrip where knowing imagery date would be extremely useful.
So it would be nice to have a mantained wiki page where you can find imagery source references.

(29 Apr '21, 10:54) Cascafico

Source code available on GitHub .