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I have a problem with exporting raster layers stored in a geopackage, to a QFIELD project. I work with version 3.4.12 of QGIS and I have version 3.5.1 of QFIELD Sync installed.

The process I follow is as follows:

  1. I convert a TIF image into a layer of a geopackage

    gdal_translate --config OGR_SQLITE_SYNCHRONOUS OFF -co  APPEND_SUBDATASET=YES -co RASTER_TABLE:foto -co TILE_FORMAT=PNG_JPEG -tr 0.5 0.5 -a_srs EPSG:25829 -of GPKG foto.tif geopackage01.gpkg
    
  2. I build the pyramids of the image

    gdaladdo --config OGR_SQLITE_SYNCHRONOUS OFF -r AVERAGE geopackage01.gpkg:foto  2 4 8 16 32 64 128 256
    
  3. I save the QGIS project, and activate the QFIELD Sync plug-in in the project synchronization configuration options. In the layers list, the one within the geopackage, has the option of no action and does not allow it to be included in the project that will be used by QFIELD.

I think the statements used to create the geopackage are correct, as it does not give any error in QGIS. If I load the original layer in TIF, I can synchronize it without problem. It does not happen to me with a layer only, but it is with any raster that I load from geopackage.

Can anyone have any idea what can happen?

2 Answers 2

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I think you need to drag & drop the GPKG with the raster into QGIS (and not open it via the QGIS filebrowser). Then it should be fine!

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If by does not allow to be used you mean rapports missing layer I may have clue. The rasters in geopackage do not support relative paths.

You have to have same project path in phone and computer or manually edit .qgs file (in text editor).

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  • At the time I solved the problem with the file browser. But now I have the problem again with QGIS 3.10.10 and QFIELD 1.5.3. Could you tell me how to modify the paths in the QGIS project? Thank you Sep 30, 2020 at 19:15
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    For .qgs file just open it in favorite text editor (e.g Notepad). Then use search and type in names of sources added to project (.tiff, .gpkg ..etc). Modify path to match locations in mobile device. If you use .qgz projects, you have to add exstra step. since it is zip file you have to extract qgs file from it, edit and return it back. Good luck
    – Radenko
    Oct 1, 2020 at 8:23
  • DO IT! Thanks, I have my pictures again. Oct 3, 2020 at 7:57

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