21 lines
875 B
Python
21 lines
875 B
Python
import numpy as np
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from scipy import ndimage
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def decimate_to(shape, image):
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"""Decimate an image to reduce its size if it's too big."""
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decimation = np.max(np.ceil(np.array(image.shape, dtype=np.float)[:len(shape)]/np.array(shape)))
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return image[::int(decimation), ::int(decimation), ...]
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def sharpness_sum_lap2(rgb_image):
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"""Return an image sharpness metric: sum(laplacian(image)**")"""
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#image_bw=np.mean(decimate_to((1000,1000), rgb_image),2)
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image_bw=np.mean(rgb_image, 2)
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image_lap=ndimage.filters.laplace(image_bw)
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return np.mean(image_lap.astype(np.float)**4)
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def sharpness_edge(image):
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"""Return a sharpness metric optimised for vertical lines"""
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gray = np.mean(image.astype(float), 2)
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n = 20
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edge = np.array([[-1]*n + [1]*n])
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return np.sum([np.sum(ndimage.filters.convolve(gray,W)**2) for W in [edge, edge.T]])
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