PIL PNG IOError

[Adam Ryan]

Hello to all,

I'm using Python Mapscript, ReportLab and PIL to generate PDF files on
Windows XP.  I generate an image using mapscript, save it, and then insert
it into my pdf 'canvas':

Canvas.drawInlineImage(myfile,x,y,w,h)

If my mapfile outputformat is gif, no problem - I get a nice pdf file.  But
if my outputformat is png, I get an IOError:

File "C:\python23\lib\site-packages\PIL\ImageFile.py", line 192, in load
IOError: unknown error when reading image file

Your thinking I'm posting to the wrong listserv right?  Well, if I take
that png file and open it up in Micro$oft Paint and then save it, my
routine then works without a problem.  So I compared the two png files
(before and after saving with Paint) with gdalinfo but got identical
results.  I did notice that there was a file size decrease after saving.
But I don't know what else could be different about the files.  Any ideas?

Here are two examples of file size reduction with output format:

OUTPUTFORMAT
  NAME png
  DRIVER "GD/PNG"
  MIMETYPE "image/png"
  IMAGEMODE PC256
  EXTENSION "png"
END

Reduction: 146kb to 137kb

outputformat
  name "png"
  driver "GD/PNG"
  imagemode "RGB"
  mimetype "image/png"
  extension "png"
End

Reduction: 272kb to 205kb

Any sugestions would be grand.  Cheers to all,

Adam