Pillow/Tests/test_imageenhance.py
2019-06-13 18:54:46 +03:00

56 lines
1.7 KiB
Python

from .helper import PillowTestCase, hopper
from PIL import Image
from PIL import ImageEnhance
class TestImageEnhance(PillowTestCase):
def test_sanity(self):
# FIXME: assert_image
# Implicit asserts no exception:
ImageEnhance.Color(hopper()).enhance(0.5)
ImageEnhance.Contrast(hopper()).enhance(0.5)
ImageEnhance.Brightness(hopper()).enhance(0.5)
ImageEnhance.Sharpness(hopper()).enhance(0.5)
def test_crash(self):
# crashes on small images
im = Image.new("RGB", (1, 1))
ImageEnhance.Sharpness(im).enhance(0.5)
def _half_transparent_image(self):
# returns an image, half transparent, half solid
im = hopper("RGB")
transparent = Image.new("L", im.size, 0)
solid = Image.new("L", (im.size[0] // 2, im.size[1]), 255)
transparent.paste(solid, (0, 0))
im.putalpha(transparent)
return im
def _check_alpha(self, im, original, op, amount):
self.assertEqual(im.getbands(), original.getbands())
self.assert_image_equal(
im.getchannel("A"),
original.getchannel("A"),
"Diff on %s: %s" % (op, amount),
)
def test_alpha(self):
# Issue https://github.com/python-pillow/Pillow/issues/899
# Is alpha preserved through image enhancement?
original = self._half_transparent_image()
for op in ["Color", "Brightness", "Contrast", "Sharpness"]:
for amount in [0, 0.5, 1.0]:
self._check_alpha(
getattr(ImageEnhance, op)(original).enhance(amount),
original,
op,
amount,
)