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
