Pillow/Tests/test_numpy.py

222 lines
7.9 KiB
Python

from PIL import Image
from .helper import PillowTestCase, hopper, unittest
try:
import numpy
except ImportError:
numpy = None
TEST_IMAGE_SIZE = (10, 10)
@unittest.skipIf(numpy is None, "Numpy is not installed")
class TestNumpy(PillowTestCase):
def test_numpy_to_image(self):
def to_image(dtype, bands=1, boolean=0):
if bands == 1:
if boolean:
data = [0, 255] * 50
else:
data = list(range(100))
a = numpy.array(data, dtype=dtype)
a.shape = TEST_IMAGE_SIZE
i = Image.fromarray(a)
if list(i.getdata()) != data:
print("data mismatch for", dtype)
else:
data = list(range(100))
a = numpy.array([[x] * bands for x in data], dtype=dtype)
a.shape = TEST_IMAGE_SIZE[0], TEST_IMAGE_SIZE[1], bands
i = Image.fromarray(a)
if list(i.getchannel(0).getdata()) != list(range(100)):
print("data mismatch for", dtype)
return i
# Check supported 1-bit integer formats
self.assert_image(to_image(numpy.bool, 1, 1), "1", TEST_IMAGE_SIZE)
self.assert_image(to_image(numpy.bool8, 1, 1), "1", TEST_IMAGE_SIZE)
# Check supported 8-bit integer formats
self.assert_image(to_image(numpy.uint8), "L", TEST_IMAGE_SIZE)
self.assert_image(to_image(numpy.uint8, 3), "RGB", TEST_IMAGE_SIZE)
self.assert_image(to_image(numpy.uint8, 4), "RGBA", TEST_IMAGE_SIZE)
self.assert_image(to_image(numpy.int8), "I", TEST_IMAGE_SIZE)
# Check non-fixed-size integer types
# These may fail, depending on the platform, since we have no native
# 64 bit int image types.
# self.assert_image(to_image(numpy.uint), "I", TEST_IMAGE_SIZE)
# self.assert_image(to_image(numpy.int), "I", TEST_IMAGE_SIZE)
# Check 16-bit integer formats
if Image._ENDIAN == "<":
self.assert_image(to_image(numpy.uint16), "I;16", TEST_IMAGE_SIZE)
else:
self.assert_image(to_image(numpy.uint16), "I;16B", TEST_IMAGE_SIZE)
self.assert_image(to_image(numpy.int16), "I", TEST_IMAGE_SIZE)
# Check 32-bit integer formats
self.assert_image(to_image(numpy.uint32), "I", TEST_IMAGE_SIZE)
self.assert_image(to_image(numpy.int32), "I", TEST_IMAGE_SIZE)
# Check 64-bit integer formats
self.assertRaises(TypeError, to_image, numpy.uint64)
self.assertRaises(TypeError, to_image, numpy.int64)
# Check floating-point formats
self.assert_image(to_image(numpy.float), "F", TEST_IMAGE_SIZE)
self.assertRaises(TypeError, to_image, numpy.float16)
self.assert_image(to_image(numpy.float32), "F", TEST_IMAGE_SIZE)
self.assert_image(to_image(numpy.float64), "F", TEST_IMAGE_SIZE)
self.assert_image(to_image(numpy.uint8, 2), "LA", (10, 10))
self.assert_image(to_image(numpy.uint8, 3), "RGB", (10, 10))
self.assert_image(to_image(numpy.uint8, 4), "RGBA", (10, 10))
# based on an erring example at
# https://stackoverflow.com/questions/10854903/what-is-causing-dimension-dependent-attributeerror-in-pil-fromarray-function
def test_3d_array(self):
size = (5, TEST_IMAGE_SIZE[0], TEST_IMAGE_SIZE[1])
a = numpy.ones(size, dtype=numpy.uint8)
self.assert_image(Image.fromarray(a[1, :, :]), "L", TEST_IMAGE_SIZE)
size = (TEST_IMAGE_SIZE[0], 5, TEST_IMAGE_SIZE[1])
a = numpy.ones(size, dtype=numpy.uint8)
self.assert_image(Image.fromarray(a[:, 1, :]), "L", TEST_IMAGE_SIZE)
size = (TEST_IMAGE_SIZE[0], TEST_IMAGE_SIZE[1], 5)
a = numpy.ones(size, dtype=numpy.uint8)
self.assert_image(Image.fromarray(a[:, :, 1]), "L", TEST_IMAGE_SIZE)
def _test_img_equals_nparray(self, img, np):
self.assertGreaterEqual(len(np.shape), 2)
np_size = np.shape[1], np.shape[0]
self.assertEqual(img.size, np_size)
px = img.load()
for x in range(0, img.size[0], int(img.size[0] / 10)):
for y in range(0, img.size[1], int(img.size[1] / 10)):
self.assert_deep_equal(px[x, y], np[y, x])
def test_16bit(self):
img = Image.open("Tests/images/16bit.cropped.tif")
np_img = numpy.array(img)
self._test_img_equals_nparray(img, np_img)
self.assertEqual(np_img.dtype, numpy.dtype("<u2"))
def test_1bit(self):
# Test that 1-bit arrays convert to numpy and back
# See: https://github.com/python-pillow/Pillow/issues/350
arr = numpy.array([[1, 0, 0, 1, 0], [0, 1, 0, 0, 0]], "u1")
img = Image.fromarray(arr * 255).convert("1")
self.assertEqual(img.mode, "1")
arr_back = numpy.array(img)
numpy.testing.assert_array_equal(arr, arr_back)
def test_save_tiff_uint16(self):
# Tests that we're getting the pixel value in the right byte order.
pixel_value = 0x1234
a = numpy.array(
[pixel_value] * TEST_IMAGE_SIZE[0] * TEST_IMAGE_SIZE[1], dtype=numpy.uint16
)
a.shape = TEST_IMAGE_SIZE
img = Image.fromarray(a)
img_px = img.load()
self.assertEqual(img_px[0, 0], pixel_value)
def test_to_array(self):
def _to_array(mode, dtype):
img = hopper(mode)
# Resize to non-square
img = img.crop((3, 0, 124, 127))
self.assertEqual(img.size, (121, 127))
np_img = numpy.array(img)
self._test_img_equals_nparray(img, np_img)
self.assertEqual(np_img.dtype, dtype)
modes = [
("L", numpy.uint8),
("I", numpy.int32),
("F", numpy.float32),
("LA", numpy.uint8),
("RGB", numpy.uint8),
("RGBA", numpy.uint8),
("RGBX", numpy.uint8),
("CMYK", numpy.uint8),
("YCbCr", numpy.uint8),
("I;16", "<u2"),
("I;16B", ">u2"),
("I;16L", "<u2"),
("HSV", numpy.uint8),
]
for mode in modes:
_to_array(*mode)
def test_point_lut(self):
# see https://github.com/python-pillow/Pillow/issues/439
data = list(range(256)) * 3
lut = numpy.array(data, dtype=numpy.uint8)
im = hopper()
im.point(lut)
def test_putdata(self):
# shouldn't segfault
# see https://github.com/python-pillow/Pillow/issues/1008
im = Image.new("F", (150, 100))
arr = numpy.zeros((15000,), numpy.float32)
im.putdata(arr)
self.assertEqual(len(im.getdata()), len(arr))
def test_roundtrip_eye(self):
for dtype in (
numpy.bool,
numpy.bool8,
numpy.int8,
numpy.int16,
numpy.int32,
numpy.uint8,
numpy.uint16,
numpy.uint32,
numpy.float,
numpy.float32,
numpy.float64,
):
arr = numpy.eye(10, dtype=dtype)
numpy.testing.assert_array_equal(arr, numpy.array(Image.fromarray(arr)))
def test_zero_size(self):
# Shouldn't cause floating point exception
# See https://github.com/python-pillow/Pillow/issues/2259
im = Image.fromarray(numpy.empty((0, 0), dtype=numpy.uint8))
self.assertEqual(im.size, (0, 0))
def test_bool(self):
# https://github.com/python-pillow/Pillow/issues/2044
a = numpy.zeros((10, 2), dtype=numpy.bool)
a[0][0] = True
im2 = Image.fromarray(a)
self.assertEqual(im2.getdata()[0], 255)
def test_no_resource_warning_for_numpy_array(self):
# https://github.com/python-pillow/Pillow/issues/835
# Arrange
from numpy import array
test_file = "Tests/images/hopper.png"
im = Image.open(test_file)
# Act/Assert
self.assert_warning(None, lambda: array(im))