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Problems loading .kmz aerial imagery

Daniel Flaim shared this problem 5 years ago
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Hi,

I am having trouble getting Locus Map Pro to display aerial maps I am producing (using Gdal-translate). The images work when using Google Earth, but not when put into the Maps folder in Locus on my phone, either in the internal memory, or on the SD card (which I would prefer). The same image can be loaded from the phone (where it doesn't work) directly into Google Earth, where it does. In the phone the attached file is 221 KB in size, but on the computer it is 222 KB.

The images don't load automatically on opening the app, and when I attempt to add them as new offline maps I get the message "This folder is already in use. Select another one".

I am using a Samsung Galaxy S5.

Any suggestions on what I might be doing wrong?

Thanks

Replies (2)

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1

Hi Daniel

how do you produce your .kmz? please describe it more detailed.

If you have one photo of your wanted area you can calibrate this inside locus

https://docs.locusmap.eu/doku.php?id=manual:user_guide:maps_tools:calibrator


inside your main "doc.kml" (unpacked .kmz) there are no infos for groundoverlays (map photos) these infos are in subfolders.


attached you find modified .kmz

copy this file to locus/mapItems and follow manual

https://docs.locusmap.eu/doku.php?id=manual:user_guide:items:management


Wolfgang

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Hi Wolfgang,

Thank-you for your reply. I use gdal-translate to produce the .kmz. This is an open-source command line utility which can be used to convert raster data between different formats. I use windows 10, and enter commands through the Powershell interface (similar to the Terminal command line interface). The command I use is as follows;

gdal_translate.exe -of KMLSUPEROVERLAY "C:\FILENAME.gpkg" "C:\FILENAME.kmz" -co FORMAT=JPEG

I think (I am not experienced with gdal) the script basically says to use gdal_translate to produce a KML superoverlay of an existing raster file at a specific location, and place the new file in a specific place, using JPEG compression format.

As I said previously, the files produced work perfectly in Google Earth, and also in QGIS.

I have many such files, and the georeferencing/calibrating process you mention is too time consuming. Perhaps I should use a different file format? Or a different utility to produce the .kmz files? Is it correct that these images should load automatically when placed in the Maps folder in Locus?

I think actually that the problem lies somewhere within the file system of Locus. I realise that there are problems using SD cards with the app, and so have uninstalled it (I had a Maps folder on the SD card), deleted all reference to Locus on the phone in both internal storage and SD card. I then re-installed the app, and when connected to my computer the files are shown in the main internal memory. The phone's file browser also shows them in internal memory. When I look in the Locus however, it shows that the entire Locus directory is in the SD card. The computer shows one locus related folder on the SD card entitled 'menion.android.locus.pro', but nothing else. Why does the phone think the files are in the SD card, and could this be causing my problems?

Thank-you again for your help.

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Good day Daniel,

I've analyzed your KMZ file, it is as balloni wrote. It contains nested NetworkLinks that defined visible content. Unfortunately this advanced technique is only partially implemented in Locus Map and such complicated task simply does not work, sorry.

If file modified by balloni works, then it is one possible option. Second is to create such "map" in supported map format that then works like regular map, like "MBTiles", that should be also supported by GDAL (https://www.gdal.org/frmt_mbtiles.html). Generate MBTile map, placed in Locus/maps directory will work without problems and will be a lot faster and without any size limits, so give it a try if possible.

Let me know if you found working solution or if there is anything I may help with.

PS: about SD card: if you need to use SD Card, here is how to do it. Otherwise I really suggest to use internal memory.

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