I have a few rasters of Landsat 8 imagery I made in GRASS and exported as geotiff files. I can load them fine in QGIS and they display correctly.

But if I save it as a project, then close and reopen QGIS and load the project, the rasters' colour maps are all wrong. There will be lots of white pixels and pixels with wrong colours. Sometimes QGIS crashes randomly with the project open. Removing the layer and re-opening them fixes it. I also notice when I go properties for one of these layers, it takes about 10-15 seconds for the window to come up.

Using 2.16.3. Rasters made in GRASS 7.0.4, with no compression, UInt16 and GDAL colour table. I think it's the colour table that is causing the problem, but I want the colour scheme preserved in the file.

| improve this question | | | | |
  • 2
    Welcome to GIS:SE @gyrojam! Have you considered creating a virtual raster and load this instead of the raster layers separately? You can try this from the menubar: Raster > Miscellaneous > Build Virtual Raster. – Joseph Oct 11 '16 at 10:53
  • That is for a mosiac? This is for overlapping rasters. I.e. a truecolour image, then a infrared colour image etc. I saved the raster in QGIS and it fixes the file, but also doubles the size. I noticed QGIS saves the file as a multi-band tiff as Byte. I guess I need to save the original file differently in GRASS. – gyrojam Oct 13 '16 at 4:53
  • Can you provide the commands you used for exporting data from GRASS? Did you export a multi-band image? How does the image render when you display the data from GRASS format? – Stefan B. Oct 24 '16 at 15:16
  • This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review – Dan C Oct 24 '16 at 15:51
  • Dan, probably a reason to review the "you can only comment with sufficient reputation rule" if you do not want that kind of "answers"... – Stefan B. Oct 25 '16 at 15:17

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.