Hi all I've got some data that should be fine (came from a known-good netCDF file) but causes PIL to write an invalid image if it is used to save in PNG format (it's happy writing GIF format).
The same code writes PNGs quite happily 99% of the time, but just occasionally we generate a netCDF that causes this bug - we don't know why. We're not sure if the problem is actually in PIL or if it might be in libpng. Anyone mind taking a look please? Test data at ftp://rsg.pml.ac.uk/rsg/benj/pil_problem/: data.npz - Numpy npz data with data that causes the issue working_data.npz - npz file from another source that works fine test_harness.py - Run this with the two test files to demonstrate the problem - the PNG generated from data.npz is corrupt. Test harness code below (just to demonstrate it's nothing complicated). TIA Ben #!/usr/bin/env python import numpy import Image def test(infile, prefix): npz = numpy.load(infile) imagedata = npz['arr_0'] palette = npz['arr_1'] out_image = Image.fromarray(imagedata, 'P') out_image.putpalette(palette) out_image.save(prefix + ".gif") # ok out_image.save(prefix + ".png") # bust # end function test("data.npz", "broken") test("working_data.npz", "working") -- Ben Taylor <b...@pml.ac.uk>, http://rsg.pml.ac.uk/ Remote Sensing Group, Plymouth Marine Laboratory Tel: +44 (0)1752 633432, Fax: +44 (0)1752 633101 Latest news: www.pml.ac.uk and @PlymouthMarine Plymouth Marine Laboratory (PML) is a company limited by guarantee registered in England & Wales, company number 4178503. Registered Charity No. 1091222. Registered Office: Prospect Place, The Hoe, Plymouth PL1 3DH, UK. This message is private and confidential. If you have received this message in error, please notify the sender and remove it from your system. You are reminded that e-mail communications are not secure and may contain viruses; PML accepts no liability for any loss or damage which may be caused by viruses. _______________________________________________ Image-SIG maillist - Image-SIG@python.org http://mail.python.org/mailman/listinfo/image-sig
