mirror of
https://github.com/wassname/scikit-image.git
synced 2026-06-28 23:10:03 +08:00
Ankit Agrawal
35 lines
963 B
Python
35 lines
963 B
Python
# TODO : Doc, Tests, PEP8 check
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import numpy as np
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from skimage.util.shape import view_as_blocks
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def downsample(image, factors, method='sum'):
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# works only if image.shape is perfectly divisible by factors
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out = view_as_blocks(image, factors)
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block_shape = out.shape
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if method == 'sum':
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for i in range(len(block_shape)/2):
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out = out.sum(-1)
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else:
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for i in range(len(block_shape)/2):
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out = out.mean(-1)
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return out
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def upsample(image, factors, method='divide'):
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f = factors
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if (f[0] - int(f[0]) != 0) or (f[1] - int(f[1]) != 0):
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raise ValueError('Use resample() for non-integer upsampling')
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out = np.zeros((f[0] * image.shape[0], f[1] * image.shape[1]))
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for i in range(out.shape[0]):
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for j in range(out.shape[1]):
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out[i][j] = (image[i / f[0]][j / f[1]])
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if method == 'divide':
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return out / float(f[0] * f[1])
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else:
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return out
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