scikit-image

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__all__ = ['slice_along_axes']
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def slice_along_axes(image, slices, axes=None, copy=False):
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    """Slice an image along given axes.
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    Parameters
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    ----------
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    image : ndarray
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        Input image.
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    slices : list of 2-tuple (a, b) where a < b.
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        For each axis in `axes`, a corresponding 2-tuple
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        ``(min_val, max_val)`` to slice with (as with Python slices,
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        ``max_val`` is non-inclusive).
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    axes : int or tuple, optional
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        Axes corresponding to the limits given in `slices`. If None,
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        axes are in ascending order, up to the length of `slices`.
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    copy : bool, optional
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        If True, ensure that the output is not a view of `image`.
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    Returns
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    -------
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    out : ndarray
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        The region of `image` corresponding to the given slices and axes.
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    Examples
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    --------
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    >>> from skimage import data
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    >>> img = data.camera()
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    >>> img.shape
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    (512, 512)
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    >>> cropped_img = slice_along_axes(img, [(0, 100)])
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    >>> cropped_img.shape
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    (100, 512)
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    >>> cropped_img = slice_along_axes(img, [(0, 100), (0, 100)])
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    >>> cropped_img.shape
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    (100, 100)
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    >>> cropped_img = slice_along_axes(img, [(0, 100), (0, 75)], axes=[1, 0])
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    >>> cropped_img.shape
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    (75, 100)
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    """
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    # empty length of bounding box detected on None
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    if not slices:
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        return image
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    if axes is None:
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        axes = list(range(image.ndim))
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        if len(axes) < len(slices):
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            raise ValueError("More `slices` than available axes")
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    elif len(axes) != len(slices):
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        raise ValueError("`axes` and `slices` must have equal length")
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    if len(axes) != len(set(axes)):
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        raise ValueError("`axes` must be unique")
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    if not all(a >= 0 and a < image.ndim for a in axes):
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        raise ValueError(
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            f"axes {axes} out of range; image has only " f"{image.ndim} dimensions"
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        )
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    _slices = [
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        slice(None),
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    ] * image.ndim
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    for (a, b), ax in zip(slices, axes):
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        if a < 0:
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            a %= image.shape[ax]
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        if b < 0:
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            b %= image.shape[ax]
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        if a > b:
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            raise ValueError(
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                f"Invalid slice ({a}, {b}): must be ordered `(min_val, max_val)`"
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            )
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        if a < 0 or b > image.shape[ax]:
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            raise ValueError(
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                f"Invalid slice ({a}, {b}) for image with dimensions {image.shape}"
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            )
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        _slices[ax] = slice(a, b)
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    image_slice = image[tuple(_slices)]
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    if copy and image_slice.base is not None:
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        image_slice = image_slice.copy()
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    return image_slice
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