scikit-image

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import numpy as np
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import pytest
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from skimage._shared import testing
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from skimage._shared._warnings import expected_warnings
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from skimage.draw import random_shapes
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def test_generates_color_images_with_correct_shape():
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    image, _ = random_shapes((128, 128), max_shapes=10)
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    assert image.shape == (128, 128, 3)
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def test_generates_gray_images_with_correct_shape():
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    image, _ = random_shapes(
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        (4567, 123), min_shapes=3, max_shapes=20, channel_axis=None
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    )
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    assert image.shape == (4567, 123)
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def test_generates_gray_images_with_correct_shape_deprecated_multichannel():
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    image, _ = random_shapes(
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        (4567, 123), min_shapes=3, max_shapes=20, channel_axis=None
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    )
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    assert image.shape == (4567, 123)
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@pytest.mark.parametrize('channel_axis', [None, 0, 1, 2])
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def test_generated_shape_for_channel_axis(channel_axis):
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    shape = (128, 64)
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    num_channels = 5
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    image, _ = random_shapes(
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        shape,
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        num_channels=num_channels,
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        min_shapes=3,
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        max_shapes=10,
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        channel_axis=channel_axis,
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    )
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    if channel_axis is None:
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        expected_shape = shape
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    else:
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        expected_shape = tuple(np.insert(shape, channel_axis, num_channels))
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    assert image.shape == expected_shape
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def test_generates_correct_bounding_boxes_for_rectangles():
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    image, labels = random_shapes((128, 128), max_shapes=1, shape='rectangle', rng=42)
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    assert len(labels) == 1
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    label, bbox = labels[0]
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    assert label == 'rectangle', label
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    crop = image[bbox[0][0] : bbox[0][1], bbox[1][0] : bbox[1][1]]
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    # The crop is filled.
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    assert (crop >= 0).all() and (crop < 255).all()
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    # The crop is complete.
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    image[bbox[0][0] : bbox[0][1], bbox[1][0] : bbox[1][1]] = 255
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    assert (image == 255).all()
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def test_generates_correct_bounding_boxes_for_triangles():
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    image, labels = random_shapes((128, 128), max_shapes=1, shape='triangle', rng=42)
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    assert len(labels) == 1
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    label, bbox = labels[0]
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    assert label == 'triangle', label
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    crop = image[bbox[0][0] : bbox[0][1], bbox[1][0] : bbox[1][1]]
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    # The crop is filled.
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    assert (crop >= 0).any() and (crop < 255).any()
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    # The crop is complete.
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    image[bbox[0][0] : bbox[0][1], bbox[1][0] : bbox[1][1]] = 255
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    assert (image == 255).all()
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def test_generates_correct_bounding_boxes_for_circles():
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    image, labels = random_shapes(
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        (43, 44), max_shapes=1, min_size=20, max_size=20, shape='circle', rng=42
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    )
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    assert len(labels) == 1
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    label, bbox = labels[0]
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    assert label == 'circle', label
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    crop = image[bbox[0][0] : bbox[0][1], bbox[1][0] : bbox[1][1]]
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    # The crop is filled.
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    assert (crop >= 0).any() and (crop < 255).any()
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    # The crop is complete.
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    image[bbox[0][0] : bbox[0][1], bbox[1][0] : bbox[1][1]] = 255
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    assert (image == 255).all()
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def test_generates_correct_bounding_boxes_for_ellipses():
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    image, labels = random_shapes(
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        (43, 44), max_shapes=1, min_size=20, max_size=20, shape='ellipse', rng=42
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    )
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    assert len(labels) == 1
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    label, bbox = labels[0]
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    assert label == 'ellipse', label
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    crop = image[bbox[0][0] : bbox[0][1], bbox[1][0] : bbox[1][1]]
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    # The crop is filled.
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    assert (crop >= 0).any() and (crop < 255).any()
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    # The crop is complete.
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    image[bbox[0][0] : bbox[0][1], bbox[1][0] : bbox[1][1]] = 255
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    assert (image == 255).all()
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def test_generate_circle_throws_when_size_too_small():
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    with testing.raises(ValueError):
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        random_shapes((64, 128), max_shapes=1, min_size=1, max_size=1, shape='circle')
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def test_generate_ellipse_throws_when_size_too_small():
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    with testing.raises(ValueError):
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        random_shapes((64, 128), max_shapes=1, min_size=1, max_size=1, shape='ellipse')
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def test_generate_triangle_throws_when_size_too_small():
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    with testing.raises(ValueError):
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        random_shapes((128, 64), max_shapes=1, min_size=1, max_size=1, shape='triangle')
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def test_can_generate_one_by_one_rectangle():
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    image, labels = random_shapes(
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        (50, 128), max_shapes=1, min_size=1, max_size=1, shape='rectangle'
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    )
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    assert len(labels) == 1
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    _, bbox = labels[0]
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    crop = image[bbox[0][0] : bbox[0][1], bbox[1][0] : bbox[1][1]]
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    # rgb
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    assert np.shape(crop) == (1, 1, 3) and np.any(crop >= 1) and np.any(crop < 255)
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def test_throws_when_intensity_range_out_of_range():
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    with testing.raises(ValueError):
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        random_shapes(
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            (1000, 1234), max_shapes=1, channel_axis=None, intensity_range=(0, 256)
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        )
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    with testing.raises(ValueError):
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        random_shapes((2, 2), max_shapes=1, intensity_range=((-1, 255),))
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def test_returns_empty_labels_and_white_image_when_cannot_fit_shape():
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    # The circle will never fit this.
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    with expected_warnings(['Could not fit']):
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        image, labels = random_shapes(
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            (10000, 10000), max_shapes=1, min_size=10000, shape='circle'
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        )
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    assert len(labels) == 0
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    assert (image == 255).all()
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def test_random_shapes_is_reproducible_with_seed():
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    random_seed = 42
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    labels = []
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    for _ in range(5):
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        _, label = random_shapes((128, 128), max_shapes=5, rng=random_seed)
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        labels.append(label)
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    assert all(other == labels[0] for other in labels[1:])
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def test_generates_white_image_when_intensity_range_255():
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    image, labels = random_shapes(
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        (128, 128), max_shapes=3, intensity_range=((255, 255),), rng=42
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    )
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    assert len(labels) > 0
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    assert (image == 255).all()
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