python-pillow/Pillow
1
1
Fork 0
mirror of https://github.com/python-pillow/Pillow.git synced 2025-11-04 01:47:47 +03:00
Code Issues Packages Projects Releases Wiki Activity

Allow alpha_composite to use LA images (#9066)

Browse Source
This commit is contained in:
Hugo van Kemenade 2025-08-27 17:42:50 +03:00 committed by GitHub
commit 9a2c5160f2
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
3 changed files with 36 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
Tests/test_image.py
View File

@ -388,6 +388,37 @@ class TestImage:
assert img_colors is not None assert img_colors is not None
assert sorted(img_colors) == expected_colors assert sorted(img_colors) == expected_colors
def test_alpha_composite_la(self) -> None:
# Arrange
expected_colors = sorted(
[
(3300, (255, 255)),
(1156, (170, 192)),
(1122, (128, 255)),
(1089, (0, 0)),
(1122, (255, 128)),
(1122, (0, 128)),
(1089, (0, 255)),
]
)
dst = Image.new("LA", size=(100, 100), color=(0, 255))
draw = ImageDraw.Draw(dst)
draw.rectangle((0, 33, 100, 66), fill=(0, 128))
draw.rectangle((0, 67, 100, 100), fill=(0, 0))
src = Image.new("LA", size=(100, 100), color=(255, 255))
draw = ImageDraw.Draw(src)
draw.rectangle((33, 0, 66, 100), fill=(255, 128))
draw.rectangle((67, 0, 100, 100), fill=(255, 0))
# Act
img = Image.alpha_composite(dst, src)
# Assert
img_colors = img.getcolors()
assert img_colors is not None
assert sorted(img_colors) == expected_colors
def test_alpha_inplace(self) -> None: def test_alpha_inplace(self) -> None:
src = Image.new("RGBA", (128, 128), "blue") src = Image.new("RGBA", (128, 128), "blue")

5
src/PIL/Image.py
View File

@ -3570,9 +3570,8 @@ def alpha_composite(im1: Image, im2: Image) -> Image:
""" """
Alpha composite im2 over im1. Alpha composite im2 over im1.
:param im1: The first image. Must have mode RGBA. :param im1: The first image. Must have mode RGBA or LA.
:param im2: The second image. Must have mode RGBA, and the same size as :param im2: The second image. Must have the same mode and size as the first image.
the first image.
:returns: An :py:class:`~PIL.Image.Image` object. :returns: An :py:class:`~PIL.Image.Image` object.
""" """

7
src/libImaging/AlphaComposite.c
View File

@ -25,13 +25,12 @@ ImagingAlphaComposite(Imaging imDst, Imaging imSrc) {
int x, y; int x, y;
/* Check arguments */ /* Check arguments */
if (!imDst || !imSrc || strcmp(imDst->mode, "RGBA") || if (!imDst || !imSrc ||
imDst->type != IMAGING_TYPE_UINT8 || imDst->bands != 4) { (strcmp(imDst->mode, "RGBA") && strcmp(imDst->mode, "LA"))) {
return ImagingError_ModeError(); return ImagingError_ModeError();
} }
if (strcmp(imDst->mode, imSrc->mode) || imDst->type != imSrc->type || if (strcmp(imDst->mode, imSrc->mode) || imDst->xsize != imSrc->xsize ||
imDst->bands != imSrc->bands || imDst->xsize != imSrc->xsize ||
imDst->ysize != imSrc->ysize) { imDst->ysize != imSrc->ysize) {
return ImagingError_Mismatch(); return ImagingError_Mismatch();
} }