R: [Gdal-dev] trivial (?) optimization for gdal.i:GDALReadRaster( )

[Vincent Schut]

Frank / Alessandro

After some playing around I have the following results: opening and reading 
gdal datasets works without problems using numarray. However, when I try to 
save a numarray dataset to a file using gdal.SaveArray, I get a segfault. I'm 
sorry but I don't know how to invoke gdb to debug a python script, so I don't 
have much more information.
I tried to dig up the SaveArray function and manually invoke its steps. It 
appears that the segfault appears in the gdal.Open function on the created 
NUMPY:::<adress> object, which is made using the gdal.OpenArray function.

Try the following very simple test program to get the segfault too:

#!/usr/bin/python

import os, sys
from numarray import *
#from Numeric import *
from gdal import *
from gdalnumeric import *

print 'Creating array...'
sys.stdout.flush()

# create a 3 band array (rgb) with some values in it:
rgbImage = reshape(arange(30000, type='UInt8'),(3,100,100))

print 'Saving array...'
sys.stdout.flush()

#SaveArray( rgbImage, 'numarray_test_1.png', 'PNG', None)
# SaveArray segfaults... split it up:]

filename = GetArrayFilename( rgbImage )
print filename # just for checking
sys.stdout.flush()

# this function creates a segfault:
dataset = Open( filename )

print 'Done...'
sys.stdout.flush()

-- 
Cheers,
-----------------------------
 Vincent Schut
 SarVision B.V.
 Wageningen, The Netherlands
 www.sarvision.com