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Questions tagged [laplacianofgaussian]

The Laplacian of Gaussian (LoG) is the generalized second order derivative of the Gaussian function. In image processing, it is applied as a linear filter to obtain a regularized (smoothed) Laplace operator. When using this tag also include the more generic [image-processing] tag if applicable, as well as the language you are coding in for context.

The Laplacian of Gaussian is defined as the Laplace operator applied to a Gaussian function. That is, it is the sum of the second order derivative of the Gaussian along each of the dimensions.

In image processing it is used where a regularized Laplacian is needed: to construct edge sharpening filters, edge detection (Marr-Hildreth), etc.

See also and .

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General Laplacian of Gaussian kernel

I am having difficulty implementing a Laplacian of Gaussian kernel. I have the following code and I am trying to implement a 9x9 kernel with sigma = 1.4. The kernel is shown on this link http://homepages.inf.ed.ac.uk/rbf/HIPR2/log.htm However, my…
NamPNQ
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Laplacian of Gaussian Blob Detection showing blobs that shouldn't be there

I am trying to write a class that uses the Laplacian of Gaussian for blob detection. Here is the class that I wrote: import cv2 as cv import numpy as np from sklearn.preprocessing import normalize from scipy import ndimage class Blob: …
Jared Tolliver
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If I add a constant value to all pixels of a single channel image, would the result of Laplacian of Gaussian (LoG) convolution remain the same?

I am working on an image processing deep learning project using tensorflow. I calculated a brightness bias to add to all pixels of an image and calculated the LoG output of it. However, the sum of all pixel values was approximately the same as it…
Harsh Motwani
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Upper limit of sharpness score

I am calculating sharpness scores of images (from same fov) using this algorithm: def calc_sharpness_score(image): image=gaussian_filter(image,sigma=3) kernel_size = 7 scale = 1 delta = 0 lplImage = cv2.Laplacian(image, cv2.CV_64F,…
Sum
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Normalization of blur of the image using Laplacian

I have an image and I am interested in computing the blurr present in the image; for that I have used openCV in build functionality called cv2.Laplacian(image). But I could able to quantify the amount of blur present in the image. Is there anyway…
acoustic python
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How to use Laplacian of Gaussian for elliptical blobs?

Currently, the Scikit image package implements Laplacian of Gaussian (LoG) to find spherical blobs. The package is here. How can one convert these Laplacian of Gaussian to an elliptical Gaussian kernel? This is required to get the non-spherical…
Tara Mishra
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How to graph/plot 2D Laplacian of Gaussian (LoG) function in MATLAB or python?

Hello. I am trying to make a 3-D graph similar to the one below, that illustrates the 2-D Laplacian of Gaussian (LoG) function. How can I accomplish this through MATLAB or python? Code snippets would be greatly appreciated. I have found that we can…
john
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What is the complexity in Marr-Hildreth (Laplacian of aGaussian) filter?

what is the drawback in Laplacian of Gaussian filter? why are we going for Difference of gaussian?
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