PIL throws exception when reading bitmap/pnm data

[Cameron Walsh]

Hi all,

I'm trying to extract the data from a bitmap or .pnm file using the
following code:

import Image
img = Image.open("test.bmp","r")
data=img.getdata()

Unfortunately I get the following exception on Linux, but not on Windows:

>>> data=img.getdata()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.5/site-packages/PIL/Image.py", line 796,
in getdata
    self.load()
  File "/usr/local/lib/python2.5/site-packages/PIL/ImageFile.py", line
147, in load
    self.map = mmap.mmap(file.fileno(), size)
EnvironmentError: [Errno 19] No such device


At this time, I cannot provide the full bitmap for copyright reasons,
but I can provide some information about the bitmap:

cameron at cameron-laptop:~$ file test.bmp
test.bmp: PC bitmap data, Windows 3.x format, 1000 x 1000 x 8

The same code works for .ppm images in the same folder:

cameron at cameron-laptop:~$ convert test.bmp test.ppm
cameron at cameron-laptop:~$ python
import Image
img=Image.open("test.ppm")
data=img.getdata()

But does not work for .pnm images in the same folder:

cameron at cameron-laptop:~$ convert test.bmp test.pnm
cameron at cameron-laptop:~$ python
import Image
img=Image.open("test.pnm")
data=img.getdata()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.5/site-packages/PIL/Image.py", line 796,
in getdata
    self.load()
  File "/usr/local/lib/python2.5/site-packages/PIL/ImageFile.py", line
147, in load
    self.map = mmap.mmap(file.fileno(), size)
EnvironmentError: [Errno 19] No such device




PIL Version on Linux and Windows:

$Id: Image.py 2337 2005-03-25 07:50:30Z fredrik $


How can I avoid this error without converting each image into a
different format?


Thanks and regards,

Cameron.