Hi Craig,
Am 08.09.2011, 13:07 Uhr, schrieb Craig Coleman (C)
<craig.cole...@ordnancesurvey.co.uk>:
Hi,
I have a really thorny problem.
I need to downsample a raster map that is 23622x23622 pixels to
7874x7874 pixels using the ANTIALIAS filter.
I have the following Python code:
import Image
img = Image.open(r"C:\temp\24bit_nd.tif")
nimg = img.resize((7874,7874),Image.ANTIALIAS)
As soon as the resize method is called, python crashes instantly. I
presume this is a memory allocation issue.
I think you may be right. Do you have the full traceback the error
produces?
Is this using a 32-bit version of Python? Do you have access to a 64-bit
system? For MS Windows there is a 64-bit PIL installer:
http://www.lfd.uci.edu/~gohlke/pythonlibs/#pil
Is there another way of performing anti-aliasing on such a large image
(its 2.7GB uncompressed although I'm using LZW for storage).
I have tried converting the file to 8bit with a palette and this
successfully downsamples but the ANTIALIAS is not performed. What am I
doing wrong?
Charlie
--
Charlie Clark
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