papyri
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bundles / skimage 0.26.1rc0.dev0+git20260530.b607368ff / skimage / transform / pyramids / pyramid_laplacian

function

skimage.transform.pyramids:pyramid_laplacian

source: /dev/scikit-image/src/skimage/transform/pyramids.py :292

Signature

def   pyramid_laplacian ( image ,  max_layer = -1 ,  downscale = 2 ,  sigma = None ,  order = 1 ,  mode = reflect ,  cval = 0 ,  preserve_range = False ,  * ,  channel_axis = None )

Summary

Yield images of the laplacian pyramid formed by the input image.

Extended Summary

Each layer contains the difference between the downsampled and the downsampled, smoothed image 

layer = resize(prev_layer) - smooth(resize(prev_layer))

Note that the first image of the pyramid will be the difference between the original, unscaled image and its smoothed version. The total number of images is max_layer + 1. In case all layers are computed, the last image is either a one-pixel image or the image where the reduction does not change its shape.

Parameters

image : ndarray

Input image.

max_layer : int, optional

Number of layers for the pyramid. 0th layer is the original image. Default is -1 which builds all possible layers.

downscale : float, optional

Downscale factor.

sigma : float, optional

Sigma for Gaussian filter. Default is 2 * downscale / 6.0 which corresponds to a filter mask twice the size of the scale factor that covers more than 99% of the Gaussian distribution.

order : int, optional

Order of splines used in interpolation of downsampling. See skimage.transform.warp for detail.

mode : {'reflect', 'constant', 'edge', 'symmetric', 'wrap'}, optional

The mode parameter determines how the array borders are handled, where cval is the value when mode is equal to 'constant'.

cval : float, optional

Value to fill past edges of input if mode is 'constant'.

preserve_range : bool, optional

Whether to keep the original range of values. Otherwise, the input image is converted according to the conventions of img_as_float. Also see https://scikit-image.org/docs/dev/user_guide/data_types.html

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.

Returns

pyramid : generator

Generator yielding pyramid layers as float images.

Aliases

  • skimage.transform.pyramid_laplacian

Referenced by

This package