o :ήcY@shdZddlmZddlZddlmZddlm Z ddl m Z m Z m Z e jdd   dddddZdS)zFilters used across multiple skimage submodules. These are defined here to avoid circular imports. The unit tests remain under skimage/filters/tests/ )IterableN)ndimage)utils)_supported_float_typeconvert_to_floatwarn)multichannel_positionnearestF@) channel_axisc Cs|jdkr|jddkr|durd} tt| d}tt|dkr(td|durOt|t s9|g|jd}t ||jdkrOt |}| ||jdt ||}t|j} |j| d d }|durpt|jtjsptd tj||||||d S) akMulti-dimensional Gaussian filter. Parameters ---------- image : array-like Input image (grayscale or color) to filter. sigma : scalar or sequence of scalars, optional Standard deviation for Gaussian kernel. The standard deviations of the Gaussian filter are given for each axis as a sequence, or as a single number, in which case it is equal for all axes. output : array, optional The ``output`` parameter passes an array in which to store the filter output. mode : {'reflect', 'constant', 'nearest', 'mirror', 'wrap'}, optional The ``mode`` parameter determines how the array borders are handled, where ``cval`` is the value when mode is equal to 'constant'. Default is 'nearest'. cval : scalar, optional Value to fill past edges of input if ``mode`` is 'constant'. Default is 0.0 multichannel : bool, optional (default: None) Whether the last axis of the image is to be interpreted as multiple channels. If True, each channel is filtered separately (channels are not mixed together). Only 3 channels are supported. If ``None``, the function will attempt to guess this, and raise a warning if ambiguous, when the array has shape (M, N, 3). This argument is deprecated: specify `channel_axis` instead. preserve_range : bool, optional If True, keep the original range of values. Otherwise, the input ``image`` is converted according to the conventions of ``img_as_float`` (Normalized first to values [-1.0 ; 1.0] or [0 ; 1.0] depending on dtype of input) For more information, see: https://scikit-image.org/docs/dev/user_guide/data_types.html truncate : float, optional Truncate the filter at this many standard deviations. channel_axis : int or None, optional If None, the image is assumed to be a grayscale (single channel) image. Otherwise, this parameter indicates which axis of the array corresponds to channels. .. versionadded:: 0.19 ``channel_axis`` was added in 0.19. Returns ------- filtered_image : ndarray the filtered array Notes ----- This function is a wrapper around :func:`scipy.ndi.gaussian_filter`. Integer arrays are converted to float. The ``output`` should be floating point data type since gaussian converts to float provided ``image``. If ``output`` is not provided, another array will be allocated and returned as the result. The multi-dimensional filter is implemented as a sequence of one-dimensional convolution filters. The intermediate arrays are stored in the same data type as the output. Therefore, for output types with a limited precision, the results may be imprecise because intermediate results may be stored with insufficient precision. Examples -------- >>> a = np.zeros((3, 3)) >>> a[1, 1] = 1 >>> a array([[0., 0., 0.], [0., 1., 0.], [0., 0., 0.]]) >>> gaussian(a, sigma=0.4) # mild smoothing array([[0.00163116, 0.03712502, 0.00163116], [0.03712502, 0.84496158, 0.03712502], [0.00163116, 0.03712502, 0.00163116]]) >>> gaussian(a, sigma=1) # more smoothing array([[0.05855018, 0.09653293, 0.05855018], [0.09653293, 0.15915589, 0.09653293], [0.05855018, 0.09653293, 0.05855018]]) >>> # Several modes are possible for handling boundaries >>> gaussian(a, sigma=1, mode='reflect') array([[0.08767308, 0.12075024, 0.08767308], [0.12075024, 0.16630671, 0.12075024], [0.08767308, 0.12075024, 0.08767308]]) >>> # For RGB images, each is filtered separately >>> from skimage.data import astronaut >>> image = astronaut() >>> filtered_img = gaussian(image, sigma=1, channel_axis=-1) NzImages with dimensions (M, N, 3) are interpreted as 2D+RGB by default. Use `multichannel=False` to interpret as 3D image with last dimension of length 3.gz)Sigma values less than zero are not validr rF)copyz&Provided output data type is not float)outputmodecvaltruncate)ndimshaperRuntimeWarningnpanyasarray ValueError isinstancerlenlistinsertrrdtypeastype issubdtypefloatingndigaussian_filter) imagesigmarrr multichannelpreserve_rangerrmsg float_dtyper->/tmp/pip-target-vg8gfxp4/lib/python/skimage/_shared/filters.pygaussians( d     r/)r Nr rNFr )__doc__collections.abcrnumpyrscipyrr%_sharedr _shared.utilsrrrdeprecate_multichannel_kwargr/r-r-r-r.s