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https://github.com/wassname/scikit-image.git
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Stefan van der Walt
85 lines
2.0 KiB
Python
85 lines
2.0 KiB
Python
"""Standard test images.
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For more images, see
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- http://sipi.usc.edu/database/database.php
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"""
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import os as _os
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from ..io import imread
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from skimage import data_dir
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def load(f):
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"""Load an image file located in the data directory.
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Parameters
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----------
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f : string
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File name.
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Returns
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-------
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img : ndarray
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Image loaded from skimage.data_dir.
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"""
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return imread(_os.path.join(data_dir, f))
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def camera():
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"""Gray-level "camera" image, often used for segmentation
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and denoising examples.
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"""
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return load("camera.png")
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def lena():
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"""Colour "Lena" image.
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The standard, yet sometimes controversial Lena test image was
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scanned from the November 1972 edition of Playboy magazine. From
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an image processing perspective, this image is useful because it
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contains smooth, textured, shaded as well as detail areas.
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"""
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return load("lena.png")
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def checkerboard():
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"""Checkerboard image.
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Checkerboards are often used in image calibration, since the
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corner-points are easy to locate. Because of the many parallel
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edges, they also visualise distortions particularly well.
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"""
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return load("chessboard_GRAY.png")
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def coins():
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"""Greek coins from Pompeii.
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This image shows several coins outlined against a gray background.
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It is especially useful in, e.g. segmentation tests, where
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individual objects need to be identified against a background.
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The background shares enough grey levels with the coins that a
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simple segmentation is not sufficient.
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Notes
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-----
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This image was downloaded from the
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`Brooklyn Museum Collection
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<http://www.brooklynmuseum.org/opencollection/archives/image/617/image>`__.
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No known copyright restrictions.
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"""
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return load("coins.png")
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def moon():
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"""Surface of the moon.
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This low-contrast image of the surface of the moon is useful for
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illustrating histogram equalization and contrast stretching.
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"""
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return load("moon.png")
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