Merci Even, I can confirm that the workaround you suggested works correctly. >From the performance I was getting beforehand, I strongly believe that the mixup happening on the overview levels was causing my hat/lr dataset to never be used at all. Thank you for the quick response, Thomas
On Mon, Jul 22, 2024 at 3:21 PM Even Rouault via gdal-dev < gdal-dev@lists.osgeo.org> wrote: > Salut Thomas, > > There were actually 2 issues: > > - contrary to what the documentation stated, OVERVIEW_0_xxxx metadata > items were simply ignored, hence you only got overviews starting at the > 1/4 reduction > > - and the documentation also lied when implying that it would > automatically add overviews of overview datasets > > Both issues are now fixed per https://github.com/OSGeo/gdal/pull/10465. > > You can workaround both issues by: > > - starting your OVERVIEW_{idx} at 1 (this will be compatible of GDAL > 3.9.2, that will be tolerant to {idx} starting at 0 or 1) > > - and you can explicitly add overviews of your hat dataset by specifying > OVERVIEW_{idx}_OPEN_OPTIONS=OVERVIEW_LEVEL=NONE to gets its full > resolution, OVERVIEW_{idx+1}_OPEN_OPTIONS=OVERVIEW_LEVEL=0 to get its > first overview, etc. (this will also be compatible of GDAL 3.9.2, since > specifying the OVERVIEW_LEVEL open option prevents other overviews to be > added) > > So something like: > > OVERVIEW_1_FACTOR=2 > OVERVIEW_2_FACTOR=4 > OVERVIEW_3_FACTOR=8 > OVERVIEW_4_FACTOR=16 > OVERVIEW_5_FACTOR=32 > OVERVIEW_6_FACTOR=64 > OVERVIEW_7_FACTOR=128 > OVERVIEW_8_DATASET=/*snip*/lr.tif > OVERVIEW_8_OPEN_OPTIONS=OVERVIEW_LEVEL=NONE > OVERVIEW_9_DATASET=/*snip*/lr.tif > OVERVIEW_9_OPEN_OPTIONS=OVERVIEW_LEVEL=0 > OVERVIEW_10_DATASET=/*snip*/lr.tif > OVERVIEW_10_OPEN_OPTIONS=OVERVIEW_LEVEL=1 > > Even > > > Hi list, > > I'm experimenting with the GTI driver and hitting an issue when trying > > to add overviews. > > I'm compiling a large number of adjacent non-overlapping tiles, each > > of which has is own bundled overviews: > > > > gdalinfo /*snip*/tile-1377-471.tif > > > > Size is 32768, 32768 > > Origin = (3.057607090103000,48.420794507110998) > > Pixel Size = (0.000004056990000,-0.000002694048000) > > Band 1 Block=512x512 Type=Byte, ColorInterp=Red > > NoData Value=0 > > Overviews: 16384x16384, 8192x8192, 4096x4096, 2048x2048, 1024x1024, > > 512x512, 256x256 > > Band 2 Block=512x512 Type=Byte, ColorInterp=Green > > NoData Value=0 > > Overviews: 16384x16384, 8192x8192, 4096x4096, 2048x2048, 1024x1024, > > 512x512, 256x256 > > Band 3 Block=512x512 Type=Byte, ColorInterp=Blue > > NoData Value=0 > > Overviews: 16384x16384, 8192x8192, 4096x4096, 2048x2048, 1024x1024, > > 512x512, 256x256 > > > > I also have a very low resolution "hat" file that covers the whole > > work area: > > > > gdalinfo /*snip*/lr.tif > > Size is 2100, 1792 > > Origin = (1.413084112150000,49.303580186365998) > > Pixel Size = (0.001045206663490,-0.000689676288000) > > Band 1 Block=256x256 Type=Byte, ColorInterp=Red > > NoData Value=0 > > Overviews: 1050x896, 525x448, 263x224, 132x112 > > Band 2 Block=256x256 Type=Byte, ColorInterp=Green > > NoData Value=0 > > Overviews: 1050x896, 525x448, 263x224, 132x112 > > Band 3 Block=256x256 Type=Byte, ColorInterp=Blue > > NoData Value=0 > > Overviews: 1050x896, 525x448, 263x224, 132x112 > > > > I would like to create a GTI dataset referencing all these tiles, and > > the "hat" dataset, and have created it like so: > > > > ogrinfo -so -al mosaic.gti.fgb: > > > > Layer name: tileindex > > Metadata: > > BAND_COUNT=3 > > DATA_TYPE=Byte > > NODATA=0 > > OVERVIEW_0_FACTOR=2 > > OVERVIEW_1_FACTOR=4 > > OVERVIEW_2_FACTOR=8 > > OVERVIEW_3_FACTOR=16 > > OVERVIEW_4_FACTOR=32 > > OVERVIEW_5_FACTOR=64 > > OVERVIEW_6_FACTOR=128 > > OVERVIEW_7_DATASET=/*snip*/lr.tif > > RESAMPLING=bilinear > > RESX=0.00000269495773407954 > > RESY=0.00000269495773407954 > > > > However when I inspect the gti dataset, the overview count is not what > > I expect: > > > > gdalinfo mosaic.gti.fgb: > > > > Size is 814460, 458598 > > Origin = (1.413084000000000,49.303579999999997) > > Pixel Size = (0.000002694957734,-0.000002694957734) > > Band 1 Block=256x256 Type=Byte, ColorInterp=Undefined > > NoData Value=0 > > Overviews: 203615x114650, 101808x57325, 50904x28663, 25452x14332, > > 12726x7166, 6363x3583, 2100x1792 > > > > Note the overview list, which I would have expected to be: > > > > 407230x229299, 203615x114650, 101808x57325, 50904x28663, 25452x14332, > > 12726x7166, 6363x3583, 2100x1792, 1050x896, 525x448, 263x224, 132x112 > > > > but is not, i.e. it is missing the first overview level of the > > individual tiles, and the overviews of the hat dataset. > > Is this a configuration issue on my end ? > > > > Thanks, > > Thomas > > > > > > > > > > _______________________________________________ > > gdal-dev mailing list > > gdal-dev@lists.osgeo.org > > https://lists.osgeo.org/mailman/listinfo/gdal-dev > > -- > http://www.spatialys.com > My software is free, but my time generally not. > > _______________________________________________ > gdal-dev mailing list > gdal-dev@lists.osgeo.org > https://lists.osgeo.org/mailman/listinfo/gdal-dev >
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