ImageMagick shipped with Ubuntu 12.10 Quantal (alpha) causes crashes

Created by: laurentes

Running the testsuite on the upcoming Ubuntu distribution, we have noticed two problems with the following tests:

user@ubuntu64--12-04:~/bob/builddebug$ ./bin/nosetests -x bob.io.test.test_examples -v
test01_video2frame (bob.io.test.test_examples.ExampleTest) ... python2.7: magick/cache-view.c:477: GetCacheViewAuthenticPixels: Assertion `id < (int) cache_view->number_threads' failed.
Aborted (core dumped)

user@ubuntu64--12-04:~/bob/builddebug$ ./bin/nosetests -x bob.visioner.test.test_scripts -v
test01_face_detect (bob.visioner.test.test_scripts.VisionerScriptTest) ... ok
test02_face_detect (bob.visioner.test.test_scripts.VisionerScriptTest) ... python2.7: magick/cache-view.c:477: GetCacheViewAuthenticPixels: Assertion `id < (int) cache_view->number_threads' failed.
Aborted (core dumped)

This seems to be related to an ImageMagick bug on version 6.7.7.*, which is (unfortunately) the version (6.7.7.10-2) that will be shipped with Ubuntu Quantal. However this has been fixed in commit and integrated in current releaases of ImageMagick.

This is related to multithreading. We need to investigate further and see if we can find a workaround.