Fixed database typo and removed unnecessary class identifier.
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5098 changed files with 952558 additions and 85 deletions
16
venv/Lib/site-packages/skimage/metrics/__init__.py
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venv/Lib/site-packages/skimage/metrics/__init__.py
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from ._adapted_rand_error import adapted_rand_error
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from ._variation_of_information import variation_of_information
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from ._contingency_table import contingency_table
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from .simple_metrics import (mean_squared_error,
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normalized_root_mse,
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peak_signal_noise_ratio)
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from ._structural_similarity import structural_similarity
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__all__ = ['adapted_rand_error',
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'variation_of_information',
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'contingency_table',
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'mean_squared_error',
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'normalized_root_mse',
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'peak_signal_noise_ratio',
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'structural_similarity'
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]
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from .._shared.utils import check_shape_equality
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from ._contingency_table import contingency_table
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__all__ = ['adapted_rand_error']
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def adapted_rand_error(image_true=None, image_test=None, *, table=None,
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ignore_labels=(0,)):
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r"""Compute Adapted Rand error as defined by the SNEMI3D contest. [1]_
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Parameters
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----------
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image_true : ndarray of int
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Ground-truth label image, same shape as im_test.
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image_test : ndarray of int
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Test image.
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table : scipy.sparse array in crs format, optional
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A contingency table built with skimage.evaluate.contingency_table.
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If None, it will be computed on the fly.
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ignore_labels : sequence of int, optional
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Labels to ignore. Any part of the true image labeled with any of these
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values will not be counted in the score.
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Returns
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-------
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are : float
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The adapted Rand error; equal to :math:`1 - \frac{2pr}{p + r}`,
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where ``p`` and ``r`` are the precision and recall described below.
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prec : float
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The adapted Rand precision: this is the number of pairs of pixels that
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have the same label in the test label image *and* in the true image,
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divided by the number in the test image.
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rec : float
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The adapted Rand recall: this is the number of pairs of pixels that
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have the same label in the test label image *and* in the true image,
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divided by the number in the true image.
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Notes
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-----
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Pixels with label 0 in the true segmentation are ignored in the score.
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References
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----------
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.. [1] Arganda-Carreras I, Turaga SC, Berger DR, et al. (2015)
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Crowdsourcing the creation of image segmentation algorithms
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for connectomics. Front. Neuroanat. 9:142.
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:DOI:`10.3389/fnana.2015.00142`
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"""
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if image_test is not None and image_true is not None:
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check_shape_equality(image_true, image_test)
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if table is None:
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p_ij = contingency_table(image_true, image_test,
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ignore_labels=ignore_labels, normalize=False)
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else:
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p_ij = table
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# Sum of the joint distribution squared
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sum_p_ij2 = p_ij.data @ p_ij.data - p_ij.sum()
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a_i = p_ij.sum(axis=1).A.ravel()
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b_i = p_ij.sum(axis=0).A.ravel()
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# Sum of squares of the test segment sizes (this is 2x the number of pairs
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# of pixels with the same label in im_test)
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sum_a2 = a_i @ a_i - a_i.sum()
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# Same for im_true
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sum_b2 = b_i @ b_i - b_i.sum()
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precision = sum_p_ij2 / sum_a2
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recall = sum_p_ij2 / sum_b2
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fscore = 2. * precision * recall / (precision + recall)
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are = 1. - fscore
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return are, precision, recall
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40
venv/Lib/site-packages/skimage/metrics/_contingency_table.py
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venv/Lib/site-packages/skimage/metrics/_contingency_table.py
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import scipy.sparse as sparse
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import numpy as np
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__all__ = ['contingency_table']
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def contingency_table(im_true, im_test, *, ignore_labels=(), normalize=False):
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"""
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Return the contingency table for all regions in matched segmentations.
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Parameters
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----------
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im_true : ndarray of int
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Ground-truth label image, same shape as im_test.
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im_test : ndarray of int
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Test image.
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ignore_labels : sequence of int, optional
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Labels to ignore. Any part of the true image labeled with any of these
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values will not be counted in the score.
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normalize : bool
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Determines if the contingency table is normalized by pixel count.
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Returns
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-------
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cont : scipy.sparse.csr_matrix
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A contingency table. `cont[i, j]` will equal the number of voxels
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labeled `i` in `im_true` and `j` in `im_test`.
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"""
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im_test_r = im_test.ravel()
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im_true_r = im_true.ravel()
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ignored = np.zeros(im_true_r.shape, np.bool)
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for label in ignore_labels:
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ignored[im_true_r == label] = True
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data = np.ones(im_true_r.shape)
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data[ignored] = 0
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if normalize:
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data = data / im_true.size
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cont = sparse.coo_matrix((data, (im_true_r, im_test_r))).tocsr()
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return cont
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232
venv/Lib/site-packages/skimage/metrics/_structural_similarity.py
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venv/Lib/site-packages/skimage/metrics/_structural_similarity.py
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from warnings import warn
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import numpy as np
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from scipy.ndimage import uniform_filter, gaussian_filter
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from ..util.dtype import dtype_range
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from ..util.arraycrop import crop
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from .._shared.utils import warn, check_shape_equality
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__all__ = ['structural_similarity']
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def structural_similarity(im1, im2,
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*,
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win_size=None, gradient=False, data_range=None,
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multichannel=False, gaussian_weights=False,
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full=False, **kwargs):
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"""
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Compute the mean structural similarity index between two images.
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Parameters
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----------
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im1, im2 : ndarray
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Images. Any dimensionality with same shape.
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win_size : int or None, optional
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The side-length of the sliding window used in comparison. Must be an
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odd value. If `gaussian_weights` is True, this is ignored and the
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window size will depend on `sigma`.
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gradient : bool, optional
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If True, also return the gradient with respect to im2.
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data_range : float, optional
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The data range of the input image (distance between minimum and
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maximum possible values). By default, this is estimated from the image
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data-type.
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multichannel : bool, optional
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If True, treat the last dimension of the array as channels. Similarity
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calculations are done independently for each channel then averaged.
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gaussian_weights : bool, optional
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If True, each patch has its mean and variance spatially weighted by a
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normalized Gaussian kernel of width sigma=1.5.
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full : bool, optional
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If True, also return the full structural similarity image.
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Other Parameters
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----------------
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use_sample_covariance : bool
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If True, normalize covariances by N-1 rather than, N where N is the
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number of pixels within the sliding window.
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K1 : float
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Algorithm parameter, K1 (small constant, see [1]_).
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K2 : float
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Algorithm parameter, K2 (small constant, see [1]_).
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sigma : float
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Standard deviation for the Gaussian when `gaussian_weights` is True.
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Returns
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-------
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mssim : float
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The mean structural similarity index over the image.
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grad : ndarray
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The gradient of the structural similarity between im1 and im2 [2]_.
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This is only returned if `gradient` is set to True.
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S : ndarray
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The full SSIM image. This is only returned if `full` is set to True.
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Notes
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-----
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To match the implementation of Wang et. al. [1]_, set `gaussian_weights`
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to True, `sigma` to 1.5, and `use_sample_covariance` to False.
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.. versionchanged:: 0.16
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This function was renamed from ``skimage.measure.compare_ssim`` to
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``skimage.metrics.structural_similarity``.
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References
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----------
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.. [1] Wang, Z., Bovik, A. C., Sheikh, H. R., & Simoncelli, E. P.
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(2004). Image quality assessment: From error visibility to
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structural similarity. IEEE Transactions on Image Processing,
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13, 600-612.
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https://ece.uwaterloo.ca/~z70wang/publications/ssim.pdf,
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:DOI:`10.1109/TIP.2003.819861`
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.. [2] Avanaki, A. N. (2009). Exact global histogram specification
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optimized for structural similarity. Optical Review, 16, 613-621.
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:arxiv:`0901.0065`
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:DOI:`10.1007/s10043-009-0119-z`
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"""
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check_shape_equality(im1, im2)
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if multichannel:
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# loop over channels
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args = dict(win_size=win_size,
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gradient=gradient,
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data_range=data_range,
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multichannel=False,
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gaussian_weights=gaussian_weights,
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full=full)
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args.update(kwargs)
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nch = im1.shape[-1]
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mssim = np.empty(nch)
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if gradient:
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G = np.empty(im1.shape)
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if full:
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S = np.empty(im1.shape)
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for ch in range(nch):
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ch_result = structural_similarity(im1[..., ch],
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im2[..., ch], **args)
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if gradient and full:
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mssim[..., ch], G[..., ch], S[..., ch] = ch_result
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elif gradient:
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mssim[..., ch], G[..., ch] = ch_result
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elif full:
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mssim[..., ch], S[..., ch] = ch_result
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else:
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mssim[..., ch] = ch_result
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mssim = mssim.mean()
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if gradient and full:
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return mssim, G, S
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elif gradient:
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return mssim, G
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elif full:
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return mssim, S
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else:
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return mssim
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K1 = kwargs.pop('K1', 0.01)
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K2 = kwargs.pop('K2', 0.03)
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sigma = kwargs.pop('sigma', 1.5)
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if K1 < 0:
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raise ValueError("K1 must be positive")
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if K2 < 0:
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raise ValueError("K2 must be positive")
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if sigma < 0:
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raise ValueError("sigma must be positive")
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use_sample_covariance = kwargs.pop('use_sample_covariance', True)
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if gaussian_weights:
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# Set to give an 11-tap filter with the default sigma of 1.5 to match
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# Wang et. al. 2004.
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truncate = 3.5
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if win_size is None:
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if gaussian_weights:
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# set win_size used by crop to match the filter size
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r = int(truncate * sigma + 0.5) # radius as in ndimage
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win_size = 2 * r + 1
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else:
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win_size = 7 # backwards compatibility
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if np.any((np.asarray(im1.shape) - win_size) < 0):
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raise ValueError(
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"win_size exceeds image extent. If the input is a multichannel "
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"(color) image, set multichannel=True.")
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if not (win_size % 2 == 1):
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raise ValueError('Window size must be odd.')
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if data_range is None:
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if im1.dtype != im2.dtype:
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warn("Inputs have mismatched dtype. Setting data_range based on "
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"im1.dtype.", stacklevel=2)
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dmin, dmax = dtype_range[im1.dtype.type]
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data_range = dmax - dmin
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ndim = im1.ndim
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if gaussian_weights:
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filter_func = gaussian_filter
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filter_args = {'sigma': sigma, 'truncate': truncate}
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else:
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filter_func = uniform_filter
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filter_args = {'size': win_size}
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# ndimage filters need floating point data
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im1 = im1.astype(np.float64)
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im2 = im2.astype(np.float64)
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NP = win_size ** ndim
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# filter has already normalized by NP
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if use_sample_covariance:
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cov_norm = NP / (NP - 1) # sample covariance
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else:
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cov_norm = 1.0 # population covariance to match Wang et. al. 2004
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# compute (weighted) means
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ux = filter_func(im1, **filter_args)
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uy = filter_func(im2, **filter_args)
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# compute (weighted) variances and covariances
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uxx = filter_func(im1 * im1, **filter_args)
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uyy = filter_func(im2 * im2, **filter_args)
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uxy = filter_func(im1 * im2, **filter_args)
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vx = cov_norm * (uxx - ux * ux)
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vy = cov_norm * (uyy - uy * uy)
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vxy = cov_norm * (uxy - ux * uy)
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R = data_range
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C1 = (K1 * R) ** 2
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C2 = (K2 * R) ** 2
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A1, A2, B1, B2 = ((2 * ux * uy + C1,
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2 * vxy + C2,
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ux ** 2 + uy ** 2 + C1,
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vx + vy + C2))
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D = B1 * B2
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S = (A1 * A2) / D
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# to avoid edge effects will ignore filter radius strip around edges
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pad = (win_size - 1) // 2
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# compute (weighted) mean of ssim
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mssim = crop(S, pad).mean()
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if gradient:
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# The following is Eqs. 7-8 of Avanaki 2009.
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grad = filter_func(A1 / D, **filter_args) * im1
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grad += filter_func(-S / B2, **filter_args) * im2
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grad += filter_func((ux * (A2 - A1) - uy * (B2 - B1) * S) / D,
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**filter_args)
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grad *= (2 / im1.size)
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if full:
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return mssim, grad, S
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else:
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return mssim, grad
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else:
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if full:
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return mssim, S
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else:
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return mssim
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import numpy as np
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import scipy.sparse as sparse
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from ._contingency_table import contingency_table
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from .._shared.utils import check_shape_equality
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__all__ = ['variation_of_information']
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def variation_of_information(image0=None, image1=None, *, table=None,
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ignore_labels=()):
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"""Return symmetric conditional entropies associated with the VI. [1]_
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The variation of information is defined as VI(X,Y) = H(X|Y) + H(Y|X).
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If X is the ground-truth segmentation, then H(X|Y) can be interpreted
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as the amount of under-segmentation and H(X|Y) as the amount
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of over-segmentation. In other words, a perfect over-segmentation
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will have H(X|Y)=0 and a perfect under-segmentation will have H(Y|X)=0.
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Parameters
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----------
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image0, image1 : ndarray of int
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Label images / segmentations, must have same shape.
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table : scipy.sparse array in csr format, optional
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A contingency table built with skimage.evaluate.contingency_table.
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If None, it will be computed with skimage.evaluate.contingency_table.
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If given, the entropies will be computed from this table and any images
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will be ignored.
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ignore_labels : sequence of int, optional
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Labels to ignore. Any part of the true image labeled with any of these
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values will not be counted in the score.
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Returns
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-------
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vi : ndarray of float, shape (2,)
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The conditional entropies of image1|image0 and image0|image1.
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References
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----------
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.. [1] Marina Meilă (2007), Comparing clusterings—an information based
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distance, Journal of Multivariate Analysis, Volume 98, Issue 5,
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Pages 873-895, ISSN 0047-259X, :DOI:`10.1016/j.jmva.2006.11.013`.
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"""
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h0g1, h1g0 = _vi_tables(image0, image1, table=table,
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ignore_labels=ignore_labels)
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# false splits, false merges
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return np.array([h1g0.sum(), h0g1.sum()])
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def _xlogx(x):
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"""Compute x * log_2(x).
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We define 0 * log_2(0) = 0
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Parameters
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----------
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x : ndarray or scipy.sparse.csc_matrix or csr_matrix
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The input array.
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Returns
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-------
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y : same type as x
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Result of x * log_2(x).
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"""
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y = x.copy()
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if isinstance(y, sparse.csc_matrix) or isinstance(y, sparse.csr_matrix):
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z = y.data
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else:
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z = np.asarray(y) # ensure np.matrix converted to np.array
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nz = z.nonzero()
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z[nz] *= np.log2(z[nz])
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return y
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def _vi_tables(im_true, im_test, table=None, ignore_labels=()):
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"""Compute probability tables used for calculating VI.
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Parameters
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----------
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im_true, im_test : ndarray of int
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Input label images, any dimensionality.
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table : csr matrix, optional
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Pre-computed contingency table.
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ignore_labels : sequence of int, optional
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Labels to ignore when computing scores.
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Returns
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-------
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hxgy, hygx : ndarray of float
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Per-segment conditional entropies of ``im_true`` given ``im_test`` and
|
||||
vice-versa.
|
||||
"""
|
||||
check_shape_equality(im_true, im_test)
|
||||
|
||||
if table is None:
|
||||
# normalize, since it is an identity op if already done
|
||||
pxy = contingency_table(
|
||||
im_true, im_test,
|
||||
ignore_labels=ignore_labels, normalize=True
|
||||
)
|
||||
|
||||
else:
|
||||
pxy = table
|
||||
|
||||
# compute marginal probabilities, converting to 1D array
|
||||
px = np.ravel(pxy.sum(axis=1))
|
||||
py = np.ravel(pxy.sum(axis=0))
|
||||
|
||||
# use sparse matrix linear algebra to compute VI
|
||||
# first, compute the inverse diagonal matrices
|
||||
px_inv = sparse.diags(_invert_nonzero(px))
|
||||
py_inv = sparse.diags(_invert_nonzero(py))
|
||||
|
||||
# then, compute the entropies
|
||||
hygx = -px @ _xlogx(px_inv @ pxy).sum(axis=1)
|
||||
hxgy = -_xlogx(pxy @ py_inv).sum(axis=0) @ py
|
||||
|
||||
return list(map(np.asarray, [hxgy, hygx]))
|
||||
|
||||
|
||||
def _invert_nonzero(arr):
|
||||
"""Compute the inverse of the non-zero elements of arr, not changing 0.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
arr : ndarray
|
||||
|
||||
Returns
|
||||
-------
|
||||
arr_inv : ndarray
|
||||
Array containing the inverse of the non-zero elements of arr, and
|
||||
zero elsewhere.
|
||||
"""
|
||||
arr_inv = arr.copy()
|
||||
nz = np.nonzero(arr)
|
||||
arr_inv[nz] = 1 / arr[nz]
|
||||
return arr_inv
|
160
venv/Lib/site-packages/skimage/metrics/simple_metrics.py
Normal file
160
venv/Lib/site-packages/skimage/metrics/simple_metrics.py
Normal file
|
@ -0,0 +1,160 @@
|
|||
import numpy as np
|
||||
from ..util.dtype import dtype_range
|
||||
from .._shared.utils import warn, check_shape_equality
|
||||
|
||||
__all__ = ['mean_squared_error',
|
||||
'normalized_root_mse',
|
||||
'peak_signal_noise_ratio',
|
||||
]
|
||||
|
||||
|
||||
def _as_floats(image0, image1):
|
||||
"""
|
||||
Promote im1, im2 to nearest appropriate floating point precision.
|
||||
"""
|
||||
float_type = np.result_type(image0.dtype, image1.dtype, np.float32)
|
||||
image0 = np.asarray(image0, dtype=float_type)
|
||||
image1 = np.asarray(image1, dtype=float_type)
|
||||
return image0, image1
|
||||
|
||||
|
||||
def mean_squared_error(image0, image1):
|
||||
"""
|
||||
Compute the mean-squared error between two images.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
image0, image1 : ndarray
|
||||
Images. Any dimensionality, must have same shape.
|
||||
|
||||
Returns
|
||||
-------
|
||||
mse : float
|
||||
The mean-squared error (MSE) metric.
|
||||
|
||||
Notes
|
||||
-----
|
||||
.. versionchanged:: 0.16
|
||||
This function was renamed from ``skimage.measure.compare_mse`` to
|
||||
``skimage.metrics.mean_squared_error``.
|
||||
|
||||
"""
|
||||
check_shape_equality(image0, image1)
|
||||
image0, image1 = _as_floats(image0, image1)
|
||||
return np.mean((image0 - image1) ** 2, dtype=np.float64)
|
||||
|
||||
|
||||
def normalized_root_mse(image_true, image_test, *, normalization='euclidean'):
|
||||
"""
|
||||
Compute the normalized root mean-squared error (NRMSE) between two
|
||||
images.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
image_true : ndarray
|
||||
Ground-truth image, same shape as im_test.
|
||||
image_test : ndarray
|
||||
Test image.
|
||||
normalization : {'euclidean', 'min-max', 'mean'}, optional
|
||||
Controls the normalization method to use in the denominator of the
|
||||
NRMSE. There is no standard method of normalization across the
|
||||
literature [1]_. The methods available here are as follows:
|
||||
|
||||
- 'euclidean' : normalize by the averaged Euclidean norm of
|
||||
``im_true``::
|
||||
|
||||
NRMSE = RMSE * sqrt(N) / || im_true ||
|
||||
|
||||
where || . || denotes the Frobenius norm and ``N = im_true.size``.
|
||||
This result is equivalent to::
|
||||
|
||||
NRMSE = || im_true - im_test || / || im_true ||.
|
||||
|
||||
- 'min-max' : normalize by the intensity range of ``im_true``.
|
||||
- 'mean' : normalize by the mean of ``im_true``
|
||||
|
||||
Returns
|
||||
-------
|
||||
nrmse : float
|
||||
The NRMSE metric.
|
||||
|
||||
Notes
|
||||
-----
|
||||
.. versionchanged:: 0.16
|
||||
This function was renamed from ``skimage.measure.compare_nrmse`` to
|
||||
``skimage.metrics.normalized_root_mse``.
|
||||
|
||||
References
|
||||
----------
|
||||
.. [1] https://en.wikipedia.org/wiki/Root-mean-square_deviation
|
||||
|
||||
"""
|
||||
check_shape_equality(image_true, image_test)
|
||||
image_true, image_test = _as_floats(image_true, image_test)
|
||||
|
||||
# Ensure that both 'Euclidean' and 'euclidean' match
|
||||
normalization = normalization.lower()
|
||||
if normalization == 'euclidean':
|
||||
denom = np.sqrt(np.mean((image_true * image_true), dtype=np.float64))
|
||||
elif normalization == 'min-max':
|
||||
denom = image_true.max() - image_true.min()
|
||||
elif normalization == 'mean':
|
||||
denom = image_true.mean()
|
||||
else:
|
||||
raise ValueError("Unsupported norm_type")
|
||||
return np.sqrt(mean_squared_error(image_true, image_test)) / denom
|
||||
|
||||
|
||||
def peak_signal_noise_ratio(image_true, image_test, *, data_range=None):
|
||||
"""
|
||||
Compute the peak signal to noise ratio (PSNR) for an image.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
image_true : ndarray
|
||||
Ground-truth image, same shape as im_test.
|
||||
image_test : ndarray
|
||||
Test image.
|
||||
data_range : int, optional
|
||||
The data range of the input image (distance between minimum and
|
||||
maximum possible values). By default, this is estimated from the image
|
||||
data-type.
|
||||
|
||||
Returns
|
||||
-------
|
||||
psnr : float
|
||||
The PSNR metric.
|
||||
|
||||
Notes
|
||||
-----
|
||||
.. versionchanged:: 0.16
|
||||
This function was renamed from ``skimage.measure.compare_psnr`` to
|
||||
``skimage.metrics.peak_signal_noise_ratio``.
|
||||
|
||||
References
|
||||
----------
|
||||
.. [1] https://en.wikipedia.org/wiki/Peak_signal-to-noise_ratio
|
||||
|
||||
"""
|
||||
check_shape_equality(image_true, image_test)
|
||||
|
||||
if data_range is None:
|
||||
if image_true.dtype != image_test.dtype:
|
||||
warn("Inputs have mismatched dtype. Setting data_range based on "
|
||||
"im_true.", stacklevel=2)
|
||||
dmin, dmax = dtype_range[image_true.dtype.type]
|
||||
true_min, true_max = np.min(image_true), np.max(image_true)
|
||||
if true_max > dmax or true_min < dmin:
|
||||
raise ValueError(
|
||||
"im_true has intensity values outside the range expected for "
|
||||
"its data type. Please manually specify the data_range")
|
||||
if true_min >= 0:
|
||||
# most common case (255 for uint8, 1 for float)
|
||||
data_range = dmax
|
||||
else:
|
||||
data_range = dmax - dmin
|
||||
|
||||
image_true, image_test = _as_floats(image_true, image_test)
|
||||
|
||||
err = mean_squared_error(image_true, image_test)
|
||||
return 10 * np.log10((data_range ** 2) / err)
|
Loading…
Add table
Add a link
Reference in a new issue