Optional copy of a raster when building pyramids - Githubissues

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Optional copy of a raster when building pyramids #13469

Open qgib opened 13 years ago

qgib commented 13 years ago

Author Name: Paolo Cavallini (@pcav) Original Redmine Issue: 3409

Redmine category:rasters Assignee: nobody -

Creating internal pyramids modifies the original file. Wouldn't it be better to rename the original file by default? Maybe adding checkbox (default True) to create backup file would be better.

qgib commented 13 years ago

Author Name: Giovanni Manghi (@gioman)

The is an option (checkbox) "build pyramids internally if possible". If the checkbox is unselected, pyramids aren't always created as an external file (so no modification to the original raster)?

qgib commented 12 years ago

Author Name: Giovanni Manghi (@gioman)

fixed_version_id was changed from Version 1.7.0 to Version 1.7.4

qgib commented 12 years ago

Author Name: Giovanni Manghi (@gioman)

fixed_version_id was changed from Version 1.7.4 to Version 2.0.0

qgib commented 11 years ago

Author Name: Pirmin Kalberer (Pirmin Kalberer)

fixed_version_id was changed from Version 2.0.0 to Future Release - Nice to have

qgib commented 7 years ago

Author Name: Giovanni Manghi (@gioman)

pull_request_patch_supplied was configured as 0
easy_fix was configured as 0

qgib commented 6 years ago

Author Name: Paolo Cavallini (@pcav)

Still true in QGIS3

description was changed from Creating internal pyramids modifies the original file. Wouldn't it be better to rename the original file by default? Maybe adding checkbox (default True) to create backup file would be better. to Creating internal pyramids modifies the original file. Wouldn't it be better to rename the original file by default? Maybe adding checkbox (default True) to create backup file would be better.

AlisterH commented 2 years ago

I struggle to see the value of keeping this ticket open, but in any case, I have a comment. Gdaladdo -clean does not shrink the file, and if either it or QGIS is then used to add overviews again the junk remains, and the new overviews are added as well. This is (or at least was) due to a limitation of libtiff. So there is always potential for input files to be bloated with old overviews that have been previously "cleaned", in which case the filesize always increases!

So perhaps what would be more useful is a tool to somehow create a truly cleaned copy of a raster without any potential junk, and without recompressing the actual image data, and you can then add new overviews to that.

This might be helpful: https://gis.stackexchange.com/questions/50281/geotiff-how-to-remove-internal-overview-without-recompression