Merge pull request #6647 from radarhere/rgb2lab

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Hugo van Kemenade 2022-10-19 10:32:03 +02:00 committed by GitHub
commit bb2016794f
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2 changed files with 24 additions and 0 deletions

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@ -248,6 +248,17 @@ def test_p2pa_palette():
assert im_pa.getpalette() == im.getpalette()
@pytest.mark.parametrize("mode", ("RGB", "RGBA", "RGBX"))
def test_rgb_lab(mode):
im = Image.new(mode, (1, 1))
converted_im = im.convert("LAB")
assert converted_im.getpixel((0, 0)) == (0, 128, 128)
im = Image.new("LAB", (1, 1), (255, 0, 0))
converted_im = im.convert(mode)
assert converted_im.getpixel((0, 0))[:3] == (0, 255, 255)
def test_matrix_illegal_conversion():
# Arrange
im = hopper("CMYK")

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@ -1042,6 +1042,19 @@ class Image:
warnings.warn("Couldn't allocate palette entry for transparency")
return new
if "LAB" in (self.mode, mode):
other_mode = mode if self.mode == "LAB" else self.mode
if other_mode in ("RGB", "RGBA", "RGBX"):
from . import ImageCms
srgb = ImageCms.createProfile("sRGB")
lab = ImageCms.createProfile("LAB")
profiles = [lab, srgb] if self.mode == "LAB" else [srgb, lab]
transform = ImageCms.buildTransform(
profiles[0], profiles[1], self.mode, mode
)
return transform.apply(self)
# colorspace conversion
if dither is None:
dither = Dither.FLOYDSTEINBERG