Pillow/Tests/test_file_webp_alpha.py
Jon Dufresne 4de5477b61 Remove unnecessary unittest.main() boilerplate from test files
With the introduction and use of pytest, it is simple and easy to
execute specific tests in isolation through documented command line
arguments. Either by specifying the module path or through the `-k
EXPRESSION` argument. There is no longer any need to provide the
boilerplate:

    if __name__ == '__main__':
        unittest.main()

To every test file. It is simply noise.

The pattern remains in test files that aren't named with `test_*` as
those files are not discovered and executed by pytest by default.
2019-02-03 10:10:16 -08:00

118 lines
3.4 KiB
Python

from .helper import unittest, PillowTestCase, hopper
from PIL import Image
try:
from PIL import _webp
except ImportError:
_webp = None
@unittest.skipIf(_webp is None, "WebP support not installed")
class TestFileWebpAlpha(PillowTestCase):
def setUp(self):
if _webp.WebPDecoderBuggyAlpha(self):
self.skipTest("Buggy early version of WebP installed, "
"not testing transparency")
def test_read_rgba(self):
"""
Can we read an RGBA mode file without error?
Does it have the bits we expect?
"""
# Generated with `cwebp transparent.png -o transparent.webp`
file_path = "Tests/images/transparent.webp"
image = Image.open(file_path)
self.assertEqual(image.mode, "RGBA")
self.assertEqual(image.size, (200, 150))
self.assertEqual(image.format, "WEBP")
image.load()
image.getdata()
image.tobytes()
target = Image.open('Tests/images/transparent.png')
self.assert_image_similar(image, target, 20.0)
def test_write_lossless_rgb(self):
"""
Can we write an RGBA mode file with lossless compression without
error? Does it have the bits we expect?
"""
temp_file = self.tempfile("temp.webp")
# temp_file = "temp.webp"
pil_image = hopper('RGBA')
mask = Image.new("RGBA", (64, 64), (128, 128, 128, 128))
# Add some partially transparent bits:
pil_image.paste(mask, (0, 0), mask)
pil_image.save(temp_file, lossless=True)
image = Image.open(temp_file)
image.load()
self.assertEqual(image.mode, "RGBA")
self.assertEqual(image.size, pil_image.size)
self.assertEqual(image.format, "WEBP")
image.load()
image.getdata()
self.assert_image_equal(image, pil_image)
def test_write_rgba(self):
"""
Can we write a RGBA mode file to webp without error.
Does it have the bits we expect?
"""
temp_file = self.tempfile("temp.webp")
pil_image = Image.new("RGBA", (10, 10), (255, 0, 0, 20))
pil_image.save(temp_file)
if _webp.WebPDecoderBuggyAlpha(self):
return
image = Image.open(temp_file)
image.load()
self.assertEqual(image.mode, "RGBA")
self.assertEqual(image.size, (10, 10))
self.assertEqual(image.format, "WEBP")
image.load()
image.getdata()
# early versions of webp are known to produce higher deviations:
# deal with it
if _webp.WebPDecoderVersion(self) <= 0x201:
self.assert_image_similar(image, pil_image, 3.0)
else:
self.assert_image_similar(image, pil_image, 1.0)
def test_write_unsupported_mode_PA(self):
"""
Saving a palette-based file with transparency to WebP format
should work, and be similar to the original file.
"""
temp_file = self.tempfile("temp.webp")
file_path = "Tests/images/transparent.gif"
Image.open(file_path).save(temp_file)
image = Image.open(temp_file)
self.assertEqual(image.mode, "RGBA")
self.assertEqual(image.size, (200, 150))
self.assertEqual(image.format, "WEBP")
image.load()
image.getdata()
target = Image.open(file_path).convert("RGBA")
self.assert_image_similar(image, target, 25.0)