Pillow/Tests/test_imageenhance.py
Jon Dufresne d50445ff30 Introduce isort to automate import ordering and formatting
Similar to the recent adoption of Black. isort is a Python utility to
sort imports alphabetically and automatically separate into sections. By
using isort, contributors can quickly and automatically conform to the
projects style without thinking. Just let the tool do it.

Uses the configuration recommended by the Black to avoid conflicts of
style.

Rewrite TestImageQt.test_deprecated to no rely on import order.
2019-07-06 16:11:35 -07:00

55 lines
1.7 KiB
Python

from PIL import Image, ImageEnhance
from .helper import PillowTestCase, hopper
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,
)