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("tes t.bmp","r")
data=img.getdat a()

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

>>data=img.getd ata()

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)
EnvironmentErro r: [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@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@cameron-laptop:~$ convert test.bmp test.ppm
cameron@cameron-laptop:~$ python
import Image
img=Image.open( "test.ppm")
data=img.getdat a()

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

cameron@cameron-laptop:~$ convert test.bmp test.pnm
cameron@cameron-laptop:~$ python
import Image
img=Image.open( "test.pnm")
data=img.getdat a()
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)
EnvironmentErro r: [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.

[Cameron Walsh]

Re: PIL throws exception when reading bitmap/pnm data

Cameron Walsh wrote:

Hi all,
>
I'm trying to extract the data from a bitmap or .pnm file using the
following code:
>
import Image
img = Image.open("tes t.bmp","r")
data=img.getdat a()
>
Unfortunately I get the following exception on Linux, but not on Windows:
>

>>>data=img.get data()

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)
EnvironmentErro r: [Errno 19] No such device
>

<SNIP>

>
>
Thanks and regards,
>
Cameron.

Hi all,

It turns out the problem only arose when the file was on an NTFS drive
mounted as NTFS-3g. Copying it to my home directory fixed the problem.

Who do I send the bug report to, the ntfs-3g or the PIL guys?

Regards,

Cameron.

[Roel Schroeven]

Re: PIL throws exception when reading bitmap/pnm data

Dennis Lee Bieber schreef:

Send a complaint to M$ requesting them to open document the NTFS
format... I've been out of the loop for a while, but the last time I
checked, NTFS was something that should be treated as read-only from
LINUX -- the recommendation was to make a small FAT-32 partition for any
data that needed to be shared.

Going off-topic, but there's another way nowadays: if your Linux
partitions use ext2 or ext3, you can use read/write them from Windows
with the file system drivers from http://www.fs-driver.org/


--
If I have been able to see further, it was only because I stood
on the shoulders of giants. -- Isaac Newton

Roel Schroeven