Pillow/Tests/test_image_quantize.py
Andrew Murray 4aa24f88d9
Added type hints to tests (#8203)
Co-authored-by: Andrew Murray <radarhere@users.noreply.github.com>
2024-07-05 11:56:24 -06:00

168 lines
4.8 KiB
Python

from __future__ import annotations
import pytest
from packaging.version import parse as parse_version
from PIL import Image, features
from .helper import assert_image_similar, hopper, is_ppc64le, skip_unless_feature
def test_sanity() -> None:
image = hopper()
converted = image.quantize()
assert converted.mode == "P"
assert_image_similar(converted.convert("RGB"), image, 10)
image = hopper()
converted = image.quantize(palette=hopper("P"))
assert converted.mode == "P"
assert_image_similar(converted.convert("RGB"), image, 60)
@skip_unless_feature("libimagequant")
def test_libimagequant_quantize() -> None:
image = hopper()
if is_ppc64le():
version = features.version_feature("libimagequant")
assert version is not None
if parse_version(version) < parse_version("4"):
pytest.skip("Fails with libimagequant earlier than 4.0.0 on ppc64le")
converted = image.quantize(100, Image.Quantize.LIBIMAGEQUANT)
assert converted.mode == "P"
assert_image_similar(converted.convert("RGB"), image, 15)
colors = converted.getcolors()
assert colors is not None
assert len(colors) == 100
def test_octree_quantize() -> None:
image = hopper()
converted = image.quantize(100, Image.Quantize.FASTOCTREE)
assert converted.mode == "P"
assert_image_similar(converted.convert("RGB"), image, 20)
colors = converted.getcolors()
assert colors is not None
assert len(colors) == 100
def test_rgba_quantize() -> None:
image = hopper("RGBA")
with pytest.raises(ValueError):
image.quantize(method=0)
assert image.quantize().convert().mode == "RGBA"
def test_quantize() -> None:
with Image.open("Tests/images/caption_6_33_22.png") as image:
image = image.convert("RGB")
converted = image.quantize()
assert converted.mode == "P"
assert_image_similar(converted.convert("RGB"), image, 1)
def test_quantize_no_dither() -> None:
image = hopper()
with Image.open("Tests/images/caption_6_33_22.png") as palette:
palette = palette.convert("P")
converted = image.quantize(dither=Image.Dither.NONE, palette=palette)
assert converted.mode == "P"
assert converted.palette.palette == palette.palette.palette
def test_quantize_no_dither2() -> None:
im = Image.new("RGB", (9, 1))
im.putdata([(p,) * 3 for p in range(0, 36, 4)])
palette = Image.new("P", (1, 1))
data = (0, 0, 0, 32, 32, 32)
palette.putpalette(data)
quantized = im.quantize(dither=Image.Dither.NONE, palette=palette)
assert tuple(quantized.palette.palette) == data
px = quantized.load()
assert px is not None
for x in range(9):
assert px[x, 0] == (0 if x < 5 else 1)
def test_quantize_dither_diff() -> None:
image = hopper()
with Image.open("Tests/images/caption_6_33_22.png") as palette:
palette = palette.convert("P")
dither = image.quantize(dither=Image.Dither.FLOYDSTEINBERG, palette=palette)
nodither = image.quantize(dither=Image.Dither.NONE, palette=palette)
assert dither.tobytes() != nodither.tobytes()
@pytest.mark.parametrize(
"method", (Image.Quantize.MEDIANCUT, Image.Quantize.MAXCOVERAGE)
)
def test_quantize_kmeans(method: Image.Quantize) -> None:
im = hopper()
no_kmeans = im.quantize(kmeans=0, method=method)
kmeans = im.quantize(kmeans=1, method=method)
assert kmeans.tobytes() != no_kmeans.tobytes()
with pytest.raises(ValueError):
im.quantize(kmeans=-1, method=method)
def test_colors() -> None:
im = hopper()
colors = 2
converted = im.quantize(colors)
assert len(converted.palette.palette) == colors * len("RGB")
def test_transparent_colors_equal() -> None:
im = Image.new("RGBA", (1, 2), (0, 0, 0, 0))
px = im.load()
assert px is not None
px[0, 1] = (255, 255, 255, 0)
converted = im.quantize()
converted_px = converted.load()
assert converted_px is not None
assert converted_px[0, 0] == converted_px[0, 1]
@pytest.mark.parametrize(
"method, color",
(
(Image.Quantize.MEDIANCUT, (0, 0, 0)),
(Image.Quantize.MAXCOVERAGE, (0, 0, 0)),
(Image.Quantize.FASTOCTREE, (0, 0, 0)),
(Image.Quantize.FASTOCTREE, (0, 0, 0, 0)),
),
)
def test_palette(method: Image.Quantize, color: tuple[int, ...]) -> None:
im = Image.new("RGBA" if len(color) == 4 else "RGB", (1, 1), color)
converted = im.quantize(method=method)
converted_px = converted.load()
assert converted_px is not None
assert converted_px[0, 0] == converted.palette.colors[color]
def test_small_palette() -> None:
# Arrange
im = hopper()
colors = (255, 0, 0, 0, 0, 255)
p = Image.new("P", (1, 1))
p.putpalette(colors)
# Act
im = im.quantize(palette=p)
# Assert
quantized_colors = im.getcolors()
assert quantized_colors is not None
assert len(quantized_colors) == 2