check_large_memory_numpy.py

import sys

from helper import unittest, PillowTestCase

# This test is not run automatically.
#
# It requires > 2gb memory for the >2 gigapixel image generated in the
# second test.  Running this automatically would amount to a denial of
# service on our testing infrastructure.  I expect this test to fail
# on any 32-bit machine, as well as any smallish things (like
# Raspberry Pis).

from PIL import Image
try:
    import numpy as np
except ImportError:
    raise unittest.SkipTest("numpy not installed")

YDIM = 32769
XDIM = 48000


@unittest.skipIf(sys.maxsize <= 2**32, "requires 64-bit system")
class LargeMemoryNumpyTest(PillowTestCase):

    def _write_png(self, xdim, ydim):
        dtype = np.uint8
        a = np.zeros((xdim, ydim), dtype=dtype)
        f = self.tempfile('temp.png')
        im = Image.fromarray(a, 'L')
        im.save(f)

    def test_large(self):
        """ succeeded prepatch"""
        self._write_png(XDIM, YDIM)

    def test_2gpx(self):
        """failed prepatch"""
        self._write_png(XDIM, XDIM)

    def test_1475(self):
        """ issue #1475 """
        self._write_png(36352, 18144)

    def test_1475_b(self):
        a = np.zeros((36352, 18144), dtype=np.float)
        im = Image.fromarray(a, mode='F')


if __name__ == '__main__':
    unittest.main()