mirror of
https://github.com/python-pillow/Pillow.git
synced 2024-09-20 19:08:58 +03:00
630 lines
24 KiB
Python
630 lines
24 KiB
Python
from __future__ import annotations
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from collections.abc import Generator
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from contextlib import contextmanager
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import pytest
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from PIL import Image, ImageDraw
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from .helper import (
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assert_image_equal,
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assert_image_similar,
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hopper,
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mark_if_feature_version,
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)
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class TestImagingResampleVulnerability:
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# see https://github.com/python-pillow/Pillow/issues/1710
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def test_overflow(self) -> None:
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im = hopper("L")
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size_too_large = 0x100000008 // 4
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size_normal = 1000 # unimportant
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for xsize, ysize in (
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(size_too_large, size_normal),
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(size_normal, size_too_large),
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):
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with pytest.raises(MemoryError):
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# any resampling filter will do here
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im.im.resize((xsize, ysize), Image.Resampling.BILINEAR)
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def test_invalid_size(self) -> None:
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im = hopper()
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# Should not crash
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im.resize((100, 100))
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with pytest.raises(ValueError):
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im.resize((-100, 100))
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with pytest.raises(ValueError):
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im.resize((100, -100))
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def test_modify_after_resizing(self) -> None:
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im = hopper("RGB")
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# get copy with same size
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copy = im.resize(im.size)
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# some in-place operation
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copy.paste("black", (0, 0, im.width // 2, im.height // 2))
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# image should be different
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assert im.tobytes() != copy.tobytes()
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class TestImagingCoreResampleAccuracy:
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def make_case(self, mode: str, size: tuple[int, int], color: int) -> Image.Image:
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"""Makes a sample image with two dark and two bright squares.
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For example:
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e0 e0 1f 1f
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e0 e0 1f 1f
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1f 1f e0 e0
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1f 1f e0 e0
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"""
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case = Image.new("L", size, 255 - color)
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rectangle = ImageDraw.Draw(case).rectangle
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rectangle((0, 0, size[0] // 2 - 1, size[1] // 2 - 1), color)
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rectangle((size[0] // 2, size[1] // 2, size[0], size[1]), color)
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return Image.merge(mode, [case] * len(mode))
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def make_sample(self, data: str, size: tuple[int, int]) -> Image.Image:
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"""Restores a sample image from given data string which contains
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hex-encoded pixels from the top left fourth of a sample.
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"""
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data = data.replace(" ", "")
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sample = Image.new("L", size)
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s_px = sample.load()
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assert s_px is not None
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w, h = size[0] // 2, size[1] // 2
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for y in range(h):
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for x in range(w):
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val = int(data[(y * w + x) * 2 : (y * w + x + 1) * 2], 16)
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s_px[x, y] = val
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s_px[size[0] - x - 1, size[1] - y - 1] = val
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s_px[x, size[1] - y - 1] = 255 - val
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s_px[size[0] - x - 1, y] = 255 - val
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return sample
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def check_case(self, case: Image.Image, sample: Image.Image) -> None:
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s_px = sample.load()
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c_px = case.load()
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assert s_px is not None
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assert c_px is not None
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for y in range(case.size[1]):
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for x in range(case.size[0]):
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if c_px[x, y] != s_px[x, y]:
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message = (
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f"\nHave: \n{self.serialize_image(case)}\n"
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f"\nExpected: \n{self.serialize_image(sample)}"
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)
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assert s_px[x, y] == c_px[x, y], message
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def serialize_image(self, image: Image.Image) -> str:
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s_px = image.load()
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assert s_px is not None
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return "\n".join(
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" ".join(f"{s_px[x, y]:02x}" for x in range(image.size[0]))
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for y in range(image.size[1])
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)
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@pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
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def test_reduce_box(self, mode: str) -> None:
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case = self.make_case(mode, (8, 8), 0xE1)
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case = case.resize((4, 4), Image.Resampling.BOX)
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# fmt: off
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data = ("e1 e1"
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"e1 e1")
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# fmt: on
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for channel in case.split():
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self.check_case(channel, self.make_sample(data, (4, 4)))
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@pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
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def test_reduce_bilinear(self, mode: str) -> None:
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case = self.make_case(mode, (8, 8), 0xE1)
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case = case.resize((4, 4), Image.Resampling.BILINEAR)
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# fmt: off
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data = ("e1 c9"
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"c9 b7")
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# fmt: on
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for channel in case.split():
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self.check_case(channel, self.make_sample(data, (4, 4)))
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@pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
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def test_reduce_hamming(self, mode: str) -> None:
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case = self.make_case(mode, (8, 8), 0xE1)
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case = case.resize((4, 4), Image.Resampling.HAMMING)
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# fmt: off
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data = ("e1 da"
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"da d3")
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# fmt: on
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for channel in case.split():
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self.check_case(channel, self.make_sample(data, (4, 4)))
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@pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
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def test_reduce_bicubic(self, mode: str) -> None:
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case = self.make_case(mode, (12, 12), 0xE1)
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case = case.resize((6, 6), Image.Resampling.BICUBIC)
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# fmt: off
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data = ("e1 e3 d4"
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"e3 e5 d6"
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"d4 d6 c9")
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# fmt: on
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for channel in case.split():
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self.check_case(channel, self.make_sample(data, (6, 6)))
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@pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
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def test_reduce_lanczos(self, mode: str) -> None:
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case = self.make_case(mode, (16, 16), 0xE1)
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case = case.resize((8, 8), Image.Resampling.LANCZOS)
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# fmt: off
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data = ("e1 e0 e4 d7"
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"e0 df e3 d6"
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"e4 e3 e7 da"
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"d7 d6 d9 ce")
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# fmt: on
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for channel in case.split():
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self.check_case(channel, self.make_sample(data, (8, 8)))
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@pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
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def test_enlarge_box(self, mode: str) -> None:
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case = self.make_case(mode, (2, 2), 0xE1)
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case = case.resize((4, 4), Image.Resampling.BOX)
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# fmt: off
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data = ("e1 e1"
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"e1 e1")
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# fmt: on
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for channel in case.split():
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self.check_case(channel, self.make_sample(data, (4, 4)))
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@pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
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def test_enlarge_bilinear(self, mode: str) -> None:
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case = self.make_case(mode, (2, 2), 0xE1)
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case = case.resize((4, 4), Image.Resampling.BILINEAR)
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# fmt: off
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data = ("e1 b0"
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"b0 98")
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# fmt: on
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for channel in case.split():
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self.check_case(channel, self.make_sample(data, (4, 4)))
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@pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
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def test_enlarge_hamming(self, mode: str) -> None:
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case = self.make_case(mode, (2, 2), 0xE1)
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case = case.resize((4, 4), Image.Resampling.HAMMING)
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# fmt: off
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data = ("e1 d2"
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"d2 c5")
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# fmt: on
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for channel in case.split():
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self.check_case(channel, self.make_sample(data, (4, 4)))
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@pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
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def test_enlarge_bicubic(self, mode: str) -> None:
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case = self.make_case(mode, (4, 4), 0xE1)
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case = case.resize((8, 8), Image.Resampling.BICUBIC)
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# fmt: off
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data = ("e1 e5 ee b9"
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"e5 e9 f3 bc"
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"ee f3 fd c1"
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"b9 bc c1 a2")
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# fmt: on
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for channel in case.split():
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self.check_case(channel, self.make_sample(data, (8, 8)))
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@pytest.mark.parametrize("mode", ("RGBX", "RGB", "La", "L"))
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def test_enlarge_lanczos(self, mode: str) -> None:
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case = self.make_case(mode, (6, 6), 0xE1)
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case = case.resize((12, 12), Image.Resampling.LANCZOS)
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data = (
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"e1 e0 db ed f5 b8"
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"e0 df da ec f3 b7"
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"db db d6 e7 ee b5"
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"ed ec e6 fb ff bf"
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"f5 f4 ee ff ff c4"
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"b8 b7 b4 bf c4 a0"
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)
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for channel in case.split():
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self.check_case(channel, self.make_sample(data, (12, 12)))
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def test_box_filter_correct_range(self) -> None:
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im = Image.new("RGB", (8, 8), "#1688ff").resize(
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(100, 100), Image.Resampling.BOX
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)
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ref = Image.new("RGB", (100, 100), "#1688ff")
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assert_image_equal(im, ref)
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class TestCoreResampleConsistency:
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def make_case(
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self, mode: str, fill: tuple[int, int, int] | float
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) -> tuple[Image.Image, float | tuple[int, ...]]:
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im = Image.new(mode, (512, 9), fill)
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px = im.load()
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assert px is not None
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return im.resize((9, 512), Image.Resampling.LANCZOS), px[0, 0]
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def run_case(self, case: tuple[Image.Image, float | tuple[int, ...]]) -> None:
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channel, color = case
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px = channel.load()
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assert px is not None
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for x in range(channel.size[0]):
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for y in range(channel.size[1]):
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if px[x, y] != color:
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message = f"{px[x, y]} != {color} for pixel {(x, y)}"
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assert px[x, y] == color, message
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def test_8u(self) -> None:
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im, color = self.make_case("RGB", (0, 64, 255))
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r, g, b = im.split()
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assert isinstance(color, tuple)
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self.run_case((r, color[0]))
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self.run_case((g, color[1]))
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self.run_case((b, color[2]))
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self.run_case(self.make_case("L", 12))
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def test_32i(self) -> None:
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self.run_case(self.make_case("I", 12))
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self.run_case(self.make_case("I", 0x7FFFFFFF))
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self.run_case(self.make_case("I", -12))
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self.run_case(self.make_case("I", -1 << 31))
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def test_32f(self) -> None:
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self.run_case(self.make_case("F", 1))
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self.run_case(self.make_case("F", 3.40282306074e38))
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self.run_case(self.make_case("F", 1.175494e-38))
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self.run_case(self.make_case("F", 1.192093e-07))
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class TestCoreResampleAlphaCorrect:
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def make_levels_case(self, mode: str) -> Image.Image:
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i = Image.new(mode, (256, 16))
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px = i.load()
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assert px is not None
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for y in range(i.size[1]):
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for x in range(i.size[0]):
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pix = [x] * len(mode)
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pix[-1] = 255 - y * 16
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px[x, y] = tuple(pix)
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return i
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def run_levels_case(self, i: Image.Image) -> None:
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px = i.load()
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assert px is not None
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for y in range(i.size[1]):
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used_colors = set()
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for x in range(i.size[0]):
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value = px[x, y]
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assert isinstance(value, tuple)
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used_colors.add(value[0])
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assert 256 == len(used_colors), (
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"All colors should be present in resized image. "
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f"Only {len(used_colors)} on line {y}."
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)
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@pytest.mark.xfail(reason="Current implementation isn't precise enough")
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def test_levels_rgba(self) -> None:
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case = self.make_levels_case("RGBA")
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self.run_levels_case(case.resize((512, 32), Image.Resampling.BOX))
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self.run_levels_case(case.resize((512, 32), Image.Resampling.BILINEAR))
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self.run_levels_case(case.resize((512, 32), Image.Resampling.HAMMING))
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self.run_levels_case(case.resize((512, 32), Image.Resampling.BICUBIC))
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self.run_levels_case(case.resize((512, 32), Image.Resampling.LANCZOS))
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@pytest.mark.xfail(reason="Current implementation isn't precise enough")
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def test_levels_la(self) -> None:
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case = self.make_levels_case("LA")
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self.run_levels_case(case.resize((512, 32), Image.Resampling.BOX))
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self.run_levels_case(case.resize((512, 32), Image.Resampling.BILINEAR))
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self.run_levels_case(case.resize((512, 32), Image.Resampling.HAMMING))
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self.run_levels_case(case.resize((512, 32), Image.Resampling.BICUBIC))
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self.run_levels_case(case.resize((512, 32), Image.Resampling.LANCZOS))
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def make_dirty_case(
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self, mode: str, clean_pixel: tuple[int, ...], dirty_pixel: tuple[int, ...]
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) -> Image.Image:
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i = Image.new(mode, (64, 64), dirty_pixel)
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px = i.load()
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assert px is not None
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xdiv4 = i.size[0] // 4
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ydiv4 = i.size[1] // 4
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for y in range(ydiv4 * 2):
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for x in range(xdiv4 * 2):
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px[x + xdiv4, y + ydiv4] = clean_pixel
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return i
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def run_dirty_case(self, i: Image.Image, clean_pixel: tuple[int, ...]) -> None:
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px = i.load()
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assert px is not None
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for y in range(i.size[1]):
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for x in range(i.size[0]):
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value = px[x, y]
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assert isinstance(value, tuple)
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if value[-1] != 0 and value[:-1] != clean_pixel:
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message = (
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f"pixel at ({x}, {y}) is different:\n{value}\n{clean_pixel}"
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)
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assert value[:3] == clean_pixel, message
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def test_dirty_pixels_rgba(self) -> None:
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case = self.make_dirty_case("RGBA", (255, 255, 0, 128), (0, 0, 255, 0))
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self.run_dirty_case(case.resize((20, 20), Image.Resampling.BOX), (255, 255, 0))
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self.run_dirty_case(
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case.resize((20, 20), Image.Resampling.BILINEAR), (255, 255, 0)
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)
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self.run_dirty_case(
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case.resize((20, 20), Image.Resampling.HAMMING), (255, 255, 0)
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)
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self.run_dirty_case(
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case.resize((20, 20), Image.Resampling.BICUBIC), (255, 255, 0)
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)
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self.run_dirty_case(
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case.resize((20, 20), Image.Resampling.LANCZOS), (255, 255, 0)
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)
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def test_dirty_pixels_la(self) -> None:
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case = self.make_dirty_case("LA", (255, 128), (0, 0))
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self.run_dirty_case(case.resize((20, 20), Image.Resampling.BOX), (255,))
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self.run_dirty_case(case.resize((20, 20), Image.Resampling.BILINEAR), (255,))
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self.run_dirty_case(case.resize((20, 20), Image.Resampling.HAMMING), (255,))
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self.run_dirty_case(case.resize((20, 20), Image.Resampling.BICUBIC), (255,))
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self.run_dirty_case(case.resize((20, 20), Image.Resampling.LANCZOS), (255,))
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class TestCoreResamplePasses:
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@contextmanager
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def count(self, diff: int) -> Generator[None, None, None]:
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count = Image.core.get_stats()["new_count"]
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yield
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assert Image.core.get_stats()["new_count"] - count == diff
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def test_horizontal(self) -> None:
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im = hopper("L")
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with self.count(1):
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im.resize((im.size[0] - 10, im.size[1]), Image.Resampling.BILINEAR)
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def test_vertical(self) -> None:
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im = hopper("L")
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with self.count(1):
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im.resize((im.size[0], im.size[1] - 10), Image.Resampling.BILINEAR)
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def test_both(self) -> None:
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im = hopper("L")
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with self.count(2):
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im.resize((im.size[0] - 10, im.size[1] - 10), Image.Resampling.BILINEAR)
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def test_box_horizontal(self) -> None:
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im = hopper("L")
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box = (20, 0, im.size[0] - 20, im.size[1])
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with self.count(1):
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# the same size, but different box
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with_box = im.resize(im.size, Image.Resampling.BILINEAR, box)
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with self.count(2):
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cropped = im.crop(box).resize(im.size, Image.Resampling.BILINEAR)
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assert_image_similar(with_box, cropped, 0.1)
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def test_box_vertical(self) -> None:
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im = hopper("L")
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box = (0, 20, im.size[0], im.size[1] - 20)
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with self.count(1):
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# the same size, but different box
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with_box = im.resize(im.size, Image.Resampling.BILINEAR, box)
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with self.count(2):
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cropped = im.crop(box).resize(im.size, Image.Resampling.BILINEAR)
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assert_image_similar(with_box, cropped, 0.1)
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class TestCoreResampleCoefficients:
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def test_reduce(self) -> None:
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test_color = 254
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for size in range(400000, 400010, 2):
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i = Image.new("L", (size, 1), 0)
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draw = ImageDraw.Draw(i)
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draw.rectangle((0, 0, i.size[0] // 2 - 1, 0), test_color)
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|
|
|
px = i.resize((5, i.size[1]), Image.Resampling.BICUBIC).load()
|
|
assert px is not None
|
|
if px[2, 0] != test_color // 2:
|
|
assert test_color // 2 == px[2, 0]
|
|
|
|
def test_non_zero_coefficients(self) -> None:
|
|
# regression test for the wrong coefficients calculation
|
|
# due to bug https://github.com/python-pillow/Pillow/issues/2161
|
|
im = Image.new("RGBA", (1280, 1280), (0x20, 0x40, 0x60, 0xFF))
|
|
histogram = im.resize((256, 256), Image.Resampling.BICUBIC).histogram()
|
|
|
|
# first channel
|
|
assert histogram[0x100 * 0 + 0x20] == 0x10000
|
|
# second channel
|
|
assert histogram[0x100 * 1 + 0x40] == 0x10000
|
|
# third channel
|
|
assert histogram[0x100 * 2 + 0x60] == 0x10000
|
|
# fourth channel
|
|
assert histogram[0x100 * 3 + 0xFF] == 0x10000
|
|
|
|
|
|
class TestCoreResampleBox:
|
|
@pytest.mark.parametrize(
|
|
"resample",
|
|
(
|
|
Image.Resampling.NEAREST,
|
|
Image.Resampling.BOX,
|
|
Image.Resampling.BILINEAR,
|
|
Image.Resampling.HAMMING,
|
|
Image.Resampling.BICUBIC,
|
|
Image.Resampling.LANCZOS,
|
|
),
|
|
)
|
|
def test_wrong_arguments(self, resample: Image.Resampling) -> None:
|
|
im = hopper()
|
|
im.resize((32, 32), resample, (0, 0, im.width, im.height))
|
|
im.resize((32, 32), resample, (20, 20, im.width, im.height))
|
|
im.resize((32, 32), resample, (20, 20, 20, 100))
|
|
im.resize((32, 32), resample, (20, 20, 100, 20))
|
|
|
|
with pytest.raises(TypeError, match="must be sequence of length 4"):
|
|
im.resize((32, 32), resample, (im.width, im.height)) # type: ignore[arg-type]
|
|
|
|
with pytest.raises(ValueError, match="can't be negative"):
|
|
im.resize((32, 32), resample, (-20, 20, 100, 100))
|
|
with pytest.raises(ValueError, match="can't be negative"):
|
|
im.resize((32, 32), resample, (20, -20, 100, 100))
|
|
|
|
with pytest.raises(ValueError, match="can't be empty"):
|
|
im.resize((32, 32), resample, (20.1, 20, 20, 100))
|
|
with pytest.raises(ValueError, match="can't be empty"):
|
|
im.resize((32, 32), resample, (20, 20.1, 100, 20))
|
|
with pytest.raises(ValueError, match="can't be empty"):
|
|
im.resize((32, 32), resample, (20.1, 20.1, 20, 20))
|
|
|
|
with pytest.raises(ValueError, match="can't exceed"):
|
|
im.resize((32, 32), resample, (0, 0, im.width + 1, im.height))
|
|
with pytest.raises(ValueError, match="can't exceed"):
|
|
im.resize((32, 32), resample, (0, 0, im.width, im.height + 1))
|
|
|
|
def resize_tiled(
|
|
self, im: Image.Image, dst_size: tuple[int, int], xtiles: int, ytiles: int
|
|
) -> Image.Image:
|
|
def split_range(
|
|
size: int, tiles: int
|
|
) -> Generator[tuple[int, int], None, None]:
|
|
scale = size / tiles
|
|
for i in range(tiles):
|
|
yield int(round(scale * i)), int(round(scale * (i + 1)))
|
|
|
|
tiled = Image.new(im.mode, dst_size)
|
|
scale = (im.size[0] / tiled.size[0], im.size[1] / tiled.size[1])
|
|
|
|
for y0, y1 in split_range(dst_size[1], ytiles):
|
|
for x0, x1 in split_range(dst_size[0], xtiles):
|
|
box = (x0 * scale[0], y0 * scale[1], x1 * scale[0], y1 * scale[1])
|
|
tile = im.resize((x1 - x0, y1 - y0), Image.Resampling.BICUBIC, box)
|
|
tiled.paste(tile, (x0, y0))
|
|
return tiled
|
|
|
|
@mark_if_feature_version(
|
|
pytest.mark.valgrind_known_error, "libjpeg_turbo", "2.0", reason="Known Failing"
|
|
)
|
|
def test_tiles(self) -> None:
|
|
with Image.open("Tests/images/flower.jpg") as im:
|
|
assert im.size == (480, 360)
|
|
dst_size = (251, 188)
|
|
reference = im.resize(dst_size, Image.Resampling.BICUBIC)
|
|
|
|
for tiles in [(1, 1), (3, 3), (9, 7), (100, 100)]:
|
|
tiled = self.resize_tiled(im, dst_size, *tiles)
|
|
assert_image_similar(reference, tiled, 0.01)
|
|
|
|
@mark_if_feature_version(
|
|
pytest.mark.valgrind_known_error, "libjpeg_turbo", "2.0", reason="Known Failing"
|
|
)
|
|
def test_subsample(self) -> None:
|
|
# This test shows advantages of the subpixel resizing
|
|
# after supersampling (e.g. during JPEG decoding).
|
|
with Image.open("Tests/images/flower.jpg") as im:
|
|
assert im.size == (480, 360)
|
|
dst_size = (48, 36)
|
|
# Reference is cropped image resized to destination
|
|
reference = im.crop((0, 0, 473, 353)).resize(
|
|
dst_size, Image.Resampling.BICUBIC
|
|
)
|
|
# Image.Resampling.BOX emulates supersampling (480 / 8 = 60, 360 / 8 = 45)
|
|
supersampled = im.resize((60, 45), Image.Resampling.BOX)
|
|
|
|
with_box = supersampled.resize(
|
|
dst_size, Image.Resampling.BICUBIC, (0, 0, 59.125, 44.125)
|
|
)
|
|
without_box = supersampled.resize(dst_size, Image.Resampling.BICUBIC)
|
|
|
|
# error with box should be much smaller than without
|
|
assert_image_similar(reference, with_box, 6)
|
|
with pytest.raises(AssertionError, match=r"difference 29\."):
|
|
assert_image_similar(reference, without_box, 5)
|
|
|
|
@pytest.mark.parametrize("mode", ("RGB", "L", "RGBA", "LA", "I", ""))
|
|
@pytest.mark.parametrize(
|
|
"resample", (Image.Resampling.NEAREST, Image.Resampling.BILINEAR)
|
|
)
|
|
def test_formats(self, mode: str, resample: Image.Resampling) -> None:
|
|
im = hopper(mode)
|
|
box = (20, 20, im.size[0] - 20, im.size[1] - 20)
|
|
with_box = im.resize((32, 32), resample, box)
|
|
cropped = im.crop(box).resize((32, 32), resample)
|
|
assert_image_similar(cropped, with_box, 0.4)
|
|
|
|
def test_passthrough(self) -> None:
|
|
# When no resize is required
|
|
im = hopper()
|
|
|
|
for size, box in [
|
|
((40, 50), (0, 0, 40, 50)),
|
|
((40, 50), (0, 10, 40, 60)),
|
|
((40, 50), (10, 0, 50, 50)),
|
|
((40, 50), (10, 20, 50, 70)),
|
|
]:
|
|
res = im.resize(size, Image.Resampling.LANCZOS, box)
|
|
assert res.size == size
|
|
assert_image_equal(res, im.crop(box), f">>> {size} {box}")
|
|
|
|
def test_no_passthrough(self) -> None:
|
|
# When resize is required
|
|
im = hopper()
|
|
|
|
for size, box in [
|
|
((40, 50), (0.4, 0.4, 40.4, 50.4)),
|
|
((40, 50), (0.4, 10.4, 40.4, 60.4)),
|
|
((40, 50), (10.4, 0.4, 50.4, 50.4)),
|
|
((40, 50), (10.4, 20.4, 50.4, 70.4)),
|
|
]:
|
|
res = im.resize(size, Image.Resampling.LANCZOS, box)
|
|
assert res.size == size
|
|
with pytest.raises(AssertionError, match=r"difference \d"):
|
|
# check that the difference at least that much
|
|
assert_image_similar(res, im.crop(box), 20, f">>> {size} {box}")
|
|
|
|
@pytest.mark.parametrize(
|
|
"flt", (Image.Resampling.NEAREST, Image.Resampling.BICUBIC)
|
|
)
|
|
def test_skip_horizontal(self, flt: Image.Resampling) -> None:
|
|
# Can skip resize for one dimension
|
|
im = hopper()
|
|
|
|
for size, box in [
|
|
((40, 50), (0, 0, 40, 90)),
|
|
((40, 50), (0, 20, 40, 90)),
|
|
((40, 50), (10, 0, 50, 90)),
|
|
((40, 50), (10, 20, 50, 90)),
|
|
]:
|
|
res = im.resize(size, flt, box)
|
|
assert res.size == size
|
|
# Borders should be slightly different
|
|
assert_image_similar(
|
|
res,
|
|
im.crop(box).resize(size, flt),
|
|
0.4,
|
|
f">>> {size} {box} {flt}",
|
|
)
|
|
|
|
@pytest.mark.parametrize(
|
|
"flt", (Image.Resampling.NEAREST, Image.Resampling.BICUBIC)
|
|
)
|
|
def test_skip_vertical(self, flt: Image.Resampling) -> None:
|
|
# Can skip resize for one dimension
|
|
im = hopper()
|
|
|
|
for size, box in [
|
|
((40, 50), (0, 0, 90, 50)),
|
|
((40, 50), (20, 0, 90, 50)),
|
|
((40, 50), (0, 10, 90, 60)),
|
|
((40, 50), (20, 10, 90, 60)),
|
|
]:
|
|
res = im.resize(size, flt, box)
|
|
assert res.size == size
|
|
# Borders should be slightly different
|
|
assert_image_similar(
|
|
res,
|
|
im.crop(box).resize(size, flt),
|
|
0.4,
|
|
f">>> {size} {box} {flt}",
|
|
)
|