Sounds good. My next question is how to write the overviews data efficiently. I see that there is a method "GDALRasterBand * GDALRasterBand::GetOverview ( int i ) ", but for that I need to deinterlace the image (copying it), and call it 4 times. Is there any trick I am missing while calling GDALRasterBand::RasterIO? Maybe some black magic with the pixel and line spaces? The images/overviews I get from the GPU are interlaced (RGBARGBA) On the other side there is "GDALDataset::RasterIO(...)", but there is not explicit way to set the overview level.
Thanks .___ ._ ..._ .. . ._. .___ .. __ . _. . __.. ... .... ._ .__ Entre dos pensamientos racionales hay infinitos pensamientos irracionales. On Tue, 13 Jul 2021 at 14:04, Even Rouault <[email protected]> wrote: > Javier, > > You can use the "NONE" resampling method in BuildOverviews() or gdaladdo > to create the overviews IFD without allocating any storage, and then you > can open the file in update mode to set whatever values you want. > APPEND_SUBDATASET=YES will not set the appropriate value for the > SubFileType TIFF tag, and thus such pages won't be recognized as overviews > > Even > Le 13/07/2021 à 13:57, Javier Jimenez Shaw a écrit : > > Hi > > I am computing the overviews of a GeoTIFF on my own (using the GPU, much > faster), and I want to include them in the tif file (also in the ovr > sidecar file). > What is the best way to do it? Just creating a multipage TIFF (I guess > with the option APPEND_SUBDATASET=YES)? Is there anything else needed > (metadata, tiff tags, etc)? > > So far I want to do it in RGBA 8 bit images. (In the future I want to do > it also in float32 images with nodata value and any number of bands, but no > hurry). > > I am using GDAL 3.3.1 > > Any help is welcome. > > Thanks. > Javier. > .___ ._ ..._ .. . ._. .___ .. __ . _. . __.. ... .... ._ .__ > Entre dos pensamientos racionales > hay infinitos pensamientos irracionales. > > > _______________________________________________ > gdal-dev mailing > [email protected]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 [email protected] https://lists.osgeo.org/mailman/listinfo/gdal-dev
