[Image-SIG] Problems with opening some PNG files

[Joonas Paalasmaa]

Python raises this exception when opening certain PNG images
with PIL. Some PNG images work fine and some doesn't. I put a
problematic image online at http://speedloop2000.com/problem.png

Python 2.2 (#28, Dec 21 2001, 12:21:22) [MSC 32 bit (Intel)] on win32
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>>> import Image
>>> im = Image.open("problem.png")
>>> im.load()
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "C:\PYTHON\PIL \ImageFile.py", line 166, in load
    raise IOError, "decoder error %d when reading image file" % e
IOError: decoder error -3 when reading image file