Pillow/Tests/test_image_quantize.py
2019-11-26 07:03:23 +11:00

68 lines
2.5 KiB
Python

from PIL import Image
from .helper import PillowTestCase, hopper
class TestImageQuantize(PillowTestCase):
def test_sanity(self):
image = hopper()
converted = image.quantize()
self.assert_image(converted, "P", converted.size)
self.assert_image_similar(converted.convert("RGB"), image, 10)
image = hopper()
converted = image.quantize(palette=hopper("P"))
self.assert_image(converted, "P", converted.size)
self.assert_image_similar(converted.convert("RGB"), image, 60)
def test_libimagequant_quantize(self):
image = hopper()
try:
converted = image.quantize(100, Image.LIBIMAGEQUANT)
except ValueError as ex:
if "dependency" in str(ex).lower():
self.skipTest("libimagequant support not available")
else:
raise
self.assert_image(converted, "P", converted.size)
self.assert_image_similar(converted.convert("RGB"), image, 15)
self.assertEqual(len(converted.getcolors()), 100)
def test_octree_quantize(self):
image = hopper()
converted = image.quantize(100, Image.FASTOCTREE)
self.assert_image(converted, "P", converted.size)
self.assert_image_similar(converted.convert("RGB"), image, 20)
self.assertEqual(len(converted.getcolors()), 100)
def test_rgba_quantize(self):
image = hopper("RGBA")
self.assertRaises(ValueError, image.quantize, method=0)
self.assertEqual(image.quantize().convert().mode, "RGBA")
def test_quantize(self):
with Image.open("Tests/images/caption_6_33_22.png") as image:
image = image.convert("RGB")
converted = image.quantize()
self.assert_image(converted, "P", converted.size)
self.assert_image_similar(converted.convert("RGB"), image, 1)
def test_quantize_no_dither(self):
image = hopper()
with Image.open("Tests/images/caption_6_33_22.png") as palette:
palette = palette.convert("P")
converted = image.quantize(dither=0, palette=palette)
self.assert_image(converted, "P", converted.size)
def test_quantize_dither_diff(self):
image = hopper()
with Image.open("Tests/images/caption_6_33_22.png") as palette:
palette = palette.convert("P")
dither = image.quantize(dither=1, palette=palette)
nodither = image.quantize(dither=0, palette=palette)
self.assertNotEqual(dither.tobytes(), nodither.tobytes())