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I've noticed that when using Google Earth Pro I can see ground elevation data even in streams a few meters wide (different elevation values along the embankment and along the creek bed), while when I try to export the data by using the free service GPS Visualizer (GPS Visualizer), the elevation data that I see in Google Earth Pro seem not to correspond to Google ones.

In fact, when I import in QGIS the GPX file created with GPS Visualizer, the points near the stream, along the embankment and along the creek bed, have the same elevation value, while in Goole Earth Pro I can see different values of elevation in very small areas, even a few meters.

I thought GPS Visualizer referred to Google Earth data for elevation values. If not, how can I export the elevation from Google Earth Pro to process the point cloud with QGIS? If I look into GPS Visualizer elevation site (GPS Visualizer), I read in the bottom that "The Google Maps API is able to return elevations for points anywhere in the world; these are usually (but not always) the same elevations you'd see in Google Earth. Google's data comes from a variety of sources and is sometimes (but not always) more accurate than the SRTM databases." Does GPS Visualizer use Google Earth elevation data or other kind of data?

PS: I attach two images to show the difference of elevation values.

Screenshot of Google Earth Pro elevation: enter image description here

Screenshot of QGIS after importing GPX file, created by GPS Visualizer, as vector layer: enter image description here

Edit: I've found this discussion very similar to mine, but without a real answer. The OCR solution doesn't satisfy me at all. I'd like to download/extract Google Earth Pro elevation data in a "standard and direct" way. Is it possible?

2 Answers 2

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Since no one answered, I provided a fairly dirty but fairly automated solution using AutoIt and Capture2Txt, inspired by the discussion mentioned above (thanks to Adamski). I post a video of the script running. It moves automatically the mouse randomly inside a rectangle defined by user and executes Capture2Txt in a loop until user presses Esc button. It writes also in a file all the coordinates and elevation captured.

Clearly it is slow because it is necessary for Capture2Txt to capture the Google Earth coordinate and elevation text (note the black polygon that eliminates transparency and makes the ocr reading much better). As you can see in the video some coordinates skip and some points (of longitude) skip because of Capture2Txt's imperfect detection of the text. However for small areas (which can be set as desired by the user) this works. Then you have to check the decimal points of the coordinates, import into spreadsheet the output file and delete the columns you don't need (like m, 32T, etc..) and finally you can import into QGIS the file with elevation values as from Google Earth. If anyone is interested in this please write, also possibly to answer me on the GPS Visualizer issue.

Google Earth elevation extractor with AutoIt and Capture2Txt

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Two things: (1) Be careful you don't confuse the Google Maps API with Google Earth Pro elevation data. They may not always be in sync as you've seen. GPS Visualizer is citing their source as the API. The API is Google's only portable data that I know of. (Please correct me if wrong! :-) (2) Good job figuring out a workaround. I was interested at one point in extracting Google Earth 3D data for a given location, but stopped trying when I saw a comment that using scraping techniques to get data out of Google Earth may be contrary to the TOC.

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  • Hi, I ask: 1) why should Google Maps elevation data be different from Google Earth elevation data? Isn't this the same company, Google? 2) if the elevation data are different, as we notice, how is the Google Earth elevation data, that seems to be more accurate, calculated/measured compared to Google Maps one? elevation is calculated with special algorithms or it is true elevation measurements of physical objects (buildings, trees, etc...)? 3) where can I find Google Earth TOC where I can read that scraping techniques are not allowed? thanks
    – Matteo
    Commented Feb 6 at 15:16

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