4

I use the OpenLayers plugin to load Google Earth Layers in Quantum GIS to digitize/identify certain features. As my work is large occassionally I have to quit Quantum GIS to resume later. The problem I face is though I save my project as a qgs file I am not able to get the dynamically updated layer of Google Earth in the next session. The Google Earth layer just appears in the top left corner of the map area in QGIS and it shows only a portion of the area I work with. I can't zoom/pan further to other places.

Also I am not in favour of using Google Earth plugin for this work as it just takes a snapshot of the scene I have zoomed onto in Google Earth.

Improve this question
2
  • Does it work to remove the google maps layer and add a new one?
    – underdark
    Commented Mar 18, 2011 at 7:53
  • well this would make sense outside of the google maps policies, e.g. any osm based approach.
    – user9668
    Commented Aug 21, 2012 at 15:00

1 Answer 1

Reset to default
3

It is against Google Earth/Maps Terms of Use to cache the tiles for offline use outside Google Earth's own caching.

I work around I use instead is to load the imagery in QGIS at a suitable scale for digitizing (1:5K is useful for my purpose). Then, import the map view File > Save as Image. You get a snapshot of the imagery within that area. Do this process to cover your whole area.

Use the GDAL tools plugin to create a VRT of all your images. Raster > Build Virtual Raster.

Use the vrt file as you image backdrop.

One problem here is that you can't get higher zooms other than what you saved beforehand. To add more tiles, repeat all the process.

I'm not sure though if this violates Google's Terms of Use (just delete this answer if it does).

Improve this answer
1
  • I am not sure about "Terms of Use" either. Again I don't cache tiles for offline usage. I just use the images as backdrop being online. One question arises now: If such usage is against the terms of use, why are such addons allowed?
    – Chethan S.
    Commented Mar 18, 2011 at 6:35

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.