Pillow/Tests/test_file_webp.py
2013-05-21 21:29:58 -07:00

114 lines
3.2 KiB
Python

from tester import *
from PIL import Image
try:
from PIL import _webp
except:
skip('webp support not installed')
def test_version():
assert_no_exception(lambda: _webp.WebPDecoderVersion())
def test_good_alpha():
assert_equal(_webp.WebPDecoderBuggyAlpha(), 0)
def test_read_rgb():
file_path = "Images/lena.webp"
image = Image.open(file_path)
assert_equal(image.mode, "RGB")
assert_equal(image.size, (128, 128))
assert_equal(image.format, "WEBP")
assert_no_exception(lambda: image.load())
assert_no_exception(lambda: image.getdata())
# generated with: dwebp -ppm ../../Images/lena.webp -o lena_webp_bits.ppm
target = Image.open('Tests/images/lena_webp_bits.ppm')
assert_image_equal(image, target)
def test_write_rgb():
"""
Can we write a RGB mode file to webp without error. Does it have the bits we
expect?
"""
temp_file = tempfile("temp.webp")
lena("RGB").save(temp_file)
image = Image.open(temp_file)
image.load()
assert_equal(image.mode, "RGB")
assert_equal(image.size, (128, 128))
assert_equal(image.format, "WEBP")
assert_no_exception(lambda: image.load())
assert_no_exception(lambda: image.getdata())
# If we're using the exact same version of webp, this test should pass.
# but it doesn't if the webp is generated on Ubuntu and tested on Fedora.
# generated with: dwebp -ppm temp.webp -o lena_webp_write.ppm
#target = Image.open('Tests/images/lena_webp_write.ppm')
#assert_image_equal(image, target)
# This test asserts that the images are similar. If the average pixel difference
# between the two images is less than the epsilon value, then we're going to
# accept that it's a reasonable lossy version of the image. The included lena images
# for webp are showing ~16 on Ubuntu, the jpegs are showing ~18.
target = lena("RGB")
assert_image_similar(image, target, 20.0)
def test_write_rgba():
"""
Can we write a RGBA mode file to webp without error. Does it have the bits we
expect?
"""
temp_file = tempfile("temp.webp")
pil_image = Image.new("RGBA", (10, 10), (255, 0, 0, 20))
pil_image.save(temp_file)
if _webp.WebPDecoderBuggyAlpha():
return
image = Image.open(temp_file)
image.load()
assert_equal(image.mode, "RGBA")
assert_equal(image.size, (10, 10))
assert_equal(image.format, "WEBP")
assert_no_exception(image.load)
assert_no_exception(image.getdata)
assert_image_similar(image, pil_image, 1.0)
if _webp.WebPDecoderBuggyAlpha():
skip("Buggy early version of webp installed, not testing transparency")
def test_read_rgba():
# Generated with `cwebp transparent.png -o transparent.webp`
file_path = "Images/transparent.webp"
image = Image.open(file_path)
assert_equal(image.mode, "RGBA")
assert_equal(image.size, (200, 150))
assert_equal(image.format, "WEBP")
assert_no_exception(lambda: image.load())
assert_no_exception(lambda: image.getdata())
orig_bytes = image.tobytes()
target = Image.open('Images/transparent.png')
assert_image_similar(image, target, 20.0)