[gdal-dev] How to specify extent of a VRTWarpedDataset in Python?

[Anton Korosov]

Hi!
we are developing software for automatic processing of satellite data 
and decided to base it mostly on GDAL-Python bindings. Can I ask you 
about options to create Warped VRT datasets in Python?

1. The command

gdalwarp -t_srs '+proj=utm +zone=24 +datum=WGS84' -of VRT -tr 1000 1000 
-te -1000000 7000000 2000000 10000000 input.tif output.vrt

creates a VRT file of subclass VRTWarpedDataset. The size, resolution 
and spatial reference is specified by the options of that command.
Is there any way I can create such VRTWarpedDataset using GDAL-Python 
bindings?

I'm afraid that with the function gdal.AutoCreateWarpedVRT() I can 
specify only spatial reference (i.e. UTM Zone) but not raster size and 
resolution. Am I right?
Of course I can edit the generated VRT file and adjust RasterXSize, 
RasterYSize, GeoTransform and DstGeoTransform manually. But is there any 
way to do that programmatically?


2. How can I convert the VRT dataset generated by AutoCreateWarpedVRT 
into a string without writing to disk? That's necessary since a VRT from 
a MERIS full swath exceeds 6 MB. Also for our applications it would be 
much more efficient to edit XML in memory and then to flush to disk with 
CreateCopy.

Thanks for support!
Anton