Pillow

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from __future__ import annotations
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from pathlib import Path
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import pytest
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from PIL import Image
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from .helper import hopper
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original = hopper().resize((32, 32)).convert("I")
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def verify(im1: Image.Image) -> None:
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    im2 = original.copy()
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    assert im1.size == im2.size
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    pix1 = im1.load()
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    pix2 = im2.load()
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    assert pix1 is not None
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    assert pix2 is not None
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    for y in range(im1.size[1]):
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        for x in range(im1.size[0]):
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            xy = x, y
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            p1 = pix1[xy]
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            p2 = pix2[xy]
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            assert (
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                p1 == p2
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            ), f"got {repr(p1)} from mode {im1.mode} at {xy}, expected {repr(p2)}"
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@pytest.mark.parametrize("mode", ("L", "I;16", "I;16B", "I;16L", "I"))
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def test_basic(tmp_path: Path, mode: str) -> None:
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    # PIL 1.1 has limited support for 16-bit image data.  Check that
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    # create/copy/transform and save works as expected.
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    im_in = original.convert(mode)
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    verify(im_in)
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    w, h = im_in.size
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    im_out = im_in.copy()
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    verify(im_out)  # copy
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    im_out = im_in.transform((w, h), Image.Transform.EXTENT, (0, 0, w, h))
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    verify(im_out)  # transform
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    filename = str(tmp_path / "temp.im")
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    im_in.save(filename)
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    with Image.open(filename) as im_out:
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        verify(im_in)
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        verify(im_out)
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    im_out = im_in.crop((0, 0, w, h))
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    verify(im_out)
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    im_out = Image.new(mode, (w, h), None)
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    im_out.paste(im_in.crop((0, 0, w // 2, h)), (0, 0))
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    im_out.paste(im_in.crop((w // 2, 0, w, h)), (w // 2, 0))
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    verify(im_in)
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    verify(im_out)
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    im_in = Image.new(mode, (1, 1), 1)
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    assert im_in.getpixel((0, 0)) == 1
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    im_in.putpixel((0, 0), 2)
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    assert im_in.getpixel((0, 0)) == 2
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    if mode == "L":
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        maximum = 255
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    else:
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        maximum = 32767
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    im_in = Image.new(mode, (1, 1), 256)
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    assert im_in.getpixel((0, 0)) == min(256, maximum)
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    im_in.putpixel((0, 0), 512)
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    assert im_in.getpixel((0, 0)) == min(512, maximum)
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def test_tobytes() -> None:
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    def tobytes(mode: str) -> bytes:
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        return Image.new(mode, (1, 1), 1).tobytes()
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    order = 1 if Image._ENDIAN == "<" else -1
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    assert tobytes("L") == b"\x01"
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    assert tobytes("I;16") == b"\x01\x00"
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    assert tobytes("I;16B") == b"\x00\x01"
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    assert tobytes("I") == b"\x01\x00\x00\x00"[::order]
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def test_convert() -> None:
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    im = original.copy()
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    for mode in ("I;16", "I;16B", "I;16N"):
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        verify(im.convert(mode))
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        verify(im.convert(mode).convert("L"))
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        verify(im.convert(mode).convert("I"))
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