Troubleshooting

Orthomosaic too big for Autodesk Civil 3D - PIX4Dmapper

Issue

In some cases, the error ".tif was not found or is not valid" is displayed when loading
orthomosaic into Autodesk Civil 3D.

Cause

The issue is related to how Autodesk handles large .tiff files. Tests have been successful when importing results of smaller projects (smaller orthomosaics) but, on the other
hand, faced the issue while importing results of larger projects (e.g. orthomosaics of more
than 500 Mb). As a consequence, the error ".tif was not found or is not valid" is displayed
and the orthomosaic cannot be imported into Autodesk.

Solution

  • Reduce the resolution of the output raster. This will substantially reduce the size of
    the orthomosaic and, in most cases, will have a marginal effect on visual quality.
  • Load each tile of the orthomosaic one by one into Autodesk. The orthomosaic tiles
    are stored here ...\3_dsm_ortho_QGIS\2_mosaic\tiles. More in the Project Folder
    Structure article.
  • Use QGIS to save the orthomosaic in LZW format:
    • Open QGIS.
    • Drag and drop the orthomosaic generated in Pix4Dmapper.
    • Right-click on the corresponding layer and click Export - Save As...
    • In the dialog, Output mode select the Rendered image option.
    • Click OK.
    • Once exported, drag and drop the new orthomosaic into the main view of Autodesk.
  • Use IrfanView to save the orthomosaic as LZW:
    • Click File > Save as...
    • Save as Type: TIF
    • On the TIFF save options window select LZW
    • Click Save.
    • Open the LZW tiff file in Autodesk.

Additionally:

  • The issue might also depend on the version of Autodesk in use, for example, we were
    able to reproduce the issue with Autodesk Civil 3D 2019.
  • BigTIFF is generated when tiles are merged. From our observations, Autodesk does not know how to handle the BigTIFF and it looks as if the orthomosaic was not LZW compressed.