[Qgis-user] Visualizing multi-page GeoTIFF in QGIS

[Even Rouault]

On lundi 11 janvier 2021 13:24:18 CET Eric Younkin - NOAA Federal wrote:
> Hello,
> 
> I have a GeoTIFF that I have created in the following manner:
> 
> gdal_translate first_grid supergrid.tif
> 
> gdal_translate second_grid supergrid.tif -co APPEND_SUBDATASET=YES
> 
> Dragging this into QGIS appears to only allow me to visualize the first
> dataset used. Is there some option to allow me to view all added pages?
> This does seem to work if I use a GeoPackage instead of a GeoTIFF.  I can
> also pull in a VRT for these TIFFs and that works.  I'm going the
> APPEND_SUBDATASET route to construct one TIFF file that will work with PROJ
> vgridshift, which appears to support multipage TIFFs.

Erik,

Looks like this is a limitation of the QGIS UI. If the GDAL driver exposes a 
valid raster when opening the file (which it does for a multi-page GeoTIFF 
file, by presenting the first page), then QGIS doesn't propose to open the 
other subdatasets. The GPKG driver is different in that when there are several 
raster tables, it doesn't expose anyone by default as a valid raster, hence 
QGIS UI proposes to select the one to open.
You may file a ticket in QGIS tracker about that, if there's not an existing 
one.

Even

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