Pillow/Tests/test_numpy.py
2022-12-21 09:29:25 +11:00

242 lines
7.0 KiB
Python

import warnings
import pytest
from PIL import Image
from .helper import assert_deep_equal, assert_image, hopper
numpy = pytest.importorskip("numpy", reason="NumPy not installed")
TEST_IMAGE_SIZE = (10, 10)
def test_numpy_to_image():
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
assert_image(to_image(bool, 1, 1), "1", TEST_IMAGE_SIZE)
assert_image(to_image(numpy.bool_, 1, 1), "1", TEST_IMAGE_SIZE)
# Check supported 8-bit integer formats
assert_image(to_image(numpy.uint8), "L", TEST_IMAGE_SIZE)
assert_image(to_image(numpy.uint8, 3), "RGB", TEST_IMAGE_SIZE)
assert_image(to_image(numpy.uint8, 4), "RGBA", TEST_IMAGE_SIZE)
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.
# assert_image(to_image(numpy.uint), "I", TEST_IMAGE_SIZE)
# assert_image(to_image(numpy.int), "I", TEST_IMAGE_SIZE)
# Check 16-bit integer formats
if Image._ENDIAN == "<":
assert_image(to_image(numpy.uint16), "I;16", TEST_IMAGE_SIZE)
else:
assert_image(to_image(numpy.uint16), "I;16B", TEST_IMAGE_SIZE)
assert_image(to_image(numpy.int16), "I", TEST_IMAGE_SIZE)
# Check 32-bit integer formats
assert_image(to_image(numpy.uint32), "I", TEST_IMAGE_SIZE)
assert_image(to_image(numpy.int32), "I", TEST_IMAGE_SIZE)
# Check 64-bit integer formats
with pytest.raises(TypeError):
to_image(numpy.uint64)
with pytest.raises(TypeError):
to_image(numpy.int64)
# Check floating-point formats
assert_image(to_image(float), "F", TEST_IMAGE_SIZE)
with pytest.raises(TypeError):
to_image(numpy.float16)
assert_image(to_image(numpy.float32), "F", TEST_IMAGE_SIZE)
assert_image(to_image(numpy.float64), "F", TEST_IMAGE_SIZE)
assert_image(to_image(numpy.uint8, 2), "LA", (10, 10))
assert_image(to_image(numpy.uint8, 3), "RGB", (10, 10))
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():
size = (5, TEST_IMAGE_SIZE[0], TEST_IMAGE_SIZE[1])
a = numpy.ones(size, dtype=numpy.uint8)
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)
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)
assert_image(Image.fromarray(a[:, :, 1]), "L", TEST_IMAGE_SIZE)
def test_1d_array():
a = numpy.ones(5, dtype=numpy.uint8)
assert_image(Image.fromarray(a), "L", (1, 5))
def _test_img_equals_nparray(img, np):
assert len(np.shape) >= 2
np_size = np.shape[1], np.shape[0]
assert 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)):
assert_deep_equal(px[x, y], np[y, x])
def test_16bit():
with Image.open("Tests/images/16bit.cropped.tif") as img:
np_img = numpy.array(img)
_test_img_equals_nparray(img, np_img)
assert np_img.dtype == numpy.dtype("<u2")
def test_1bit():
# 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")
assert img.mode == "1"
arr_back = numpy.array(img)
numpy.testing.assert_array_equal(arr, arr_back)
def test_save_tiff_uint16():
# 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()
assert img_px[0, 0] == pixel_value
@pytest.mark.parametrize(
"mode, dtype",
(
("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),
),
)
def test_to_array(mode, dtype):
img = hopper(mode)
# Resize to non-square
img = img.crop((3, 0, 124, 127))
assert img.size == (121, 127)
np_img = numpy.array(img)
_test_img_equals_nparray(img, np_img)
assert np_img.dtype == dtype
def test_point_lut():
# 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():
# 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)
assert len(im.getdata()) == len(arr)
@pytest.mark.parametrize(
"dtype",
(
bool,
numpy.bool_,
numpy.int8,
numpy.int16,
numpy.int32,
numpy.uint8,
numpy.uint16,
numpy.uint32,
float,
numpy.float32,
numpy.float64,
),
)
def test_roundtrip_eye(dtype):
arr = numpy.eye(10, dtype=dtype)
numpy.testing.assert_array_equal(arr, numpy.array(Image.fromarray(arr)))
def test_zero_size():
# 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))
assert im.size == (0, 0)
def test_bool():
# https://github.com/python-pillow/Pillow/issues/2044
a = numpy.zeros((10, 2), dtype=bool)
a[0][0] = True
im2 = Image.fromarray(a)
assert im2.getdata()[0] == 255
def test_no_resource_warning_for_numpy_array():
# https://github.com/python-pillow/Pillow/issues/835
# Arrange
from numpy import array
test_file = "Tests/images/hopper.png"
with Image.open(test_file) as im:
# Act/Assert
with warnings.catch_warnings():
array(im)