Pillow/Tests/test_image_crop.py

104 lines
3.2 KiB
Python

from PIL import Image
from .helper import PillowTestCase, assert_image_equal, hopper
class TestImageCrop(PillowTestCase):
def test_crop(self):
def crop(mode):
im = hopper(mode)
assert_image_equal(im.crop(), im)
cropped = im.crop((50, 50, 100, 100))
self.assertEqual(cropped.mode, mode)
self.assertEqual(cropped.size, (50, 50))
for mode in "1", "P", "L", "RGB", "I", "F":
crop(mode)
def test_wide_crop(self):
def crop(*bbox):
i = im.crop(bbox)
h = i.histogram()
while h and not h[-1]:
del h[-1]
return tuple(h)
im = Image.new("L", (100, 100), 1)
self.assertEqual(crop(0, 0, 100, 100), (0, 10000))
self.assertEqual(crop(25, 25, 75, 75), (0, 2500))
# sides
self.assertEqual(crop(-25, 0, 25, 50), (1250, 1250))
self.assertEqual(crop(0, -25, 50, 25), (1250, 1250))
self.assertEqual(crop(75, 0, 125, 50), (1250, 1250))
self.assertEqual(crop(0, 75, 50, 125), (1250, 1250))
self.assertEqual(crop(-25, 25, 125, 75), (2500, 5000))
self.assertEqual(crop(25, -25, 75, 125), (2500, 5000))
# corners
self.assertEqual(crop(-25, -25, 25, 25), (1875, 625))
self.assertEqual(crop(75, -25, 125, 25), (1875, 625))
self.assertEqual(crop(75, 75, 125, 125), (1875, 625))
self.assertEqual(crop(-25, 75, 25, 125), (1875, 625))
def test_negative_crop(self):
# Check negative crop size (@PIL171)
im = Image.new("L", (512, 512))
im = im.crop((400, 400, 200, 200))
self.assertEqual(im.size, (0, 0))
self.assertEqual(len(im.getdata()), 0)
self.assertRaises(IndexError, lambda: im.getdata()[0])
def test_crop_float(self):
# Check cropping floats are rounded to nearest integer
# https://github.com/python-pillow/Pillow/issues/1744
# Arrange
im = Image.new("RGB", (10, 10))
self.assertEqual(im.size, (10, 10))
# Act
cropped = im.crop((0.9, 1.1, 4.2, 5.8))
# Assert
self.assertEqual(cropped.size, (3, 5))
def test_crop_crash(self):
# Image.crop crashes prepatch with an access violation
# apparently a use after free on windows, see
# https://github.com/python-pillow/Pillow/issues/1077
test_img = "Tests/images/bmp/g/pal8-0.bmp"
extents = (1, 1, 10, 10)
# works prepatch
with Image.open(test_img) as img:
img2 = img.crop(extents)
img2.load()
# fail prepatch
with Image.open(test_img) as img:
img = img.crop(extents)
img.load()
def test_crop_zero(self):
im = Image.new("RGB", (0, 0), "white")
cropped = im.crop((0, 0, 0, 0))
self.assertEqual(cropped.size, (0, 0))
cropped = im.crop((10, 10, 20, 20))
self.assertEqual(cropped.size, (10, 10))
self.assertEqual(cropped.getdata()[0], (0, 0, 0))
im = Image.new("RGB", (0, 0))
cropped = im.crop((10, 10, 20, 20))
self.assertEqual(cropped.size, (10, 10))
self.assertEqual(cropped.getdata()[2], (0, 0, 0))