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Questions tagged [gaussianblur]

In image processing, a Gaussian blur (also known as Gaussian smoothing) is the result of blurring an image by a Gaussian function (named after mathematician and scientist Carl Friedrich Gauss).

Gaussian Blur is a simple algorithm of blurring. In image processing, a Gaussian blur (also known as Gaussian smoothing) is the result of blurring an image by a Gaussian function (named after mathematician and scientist Carl Friedrich Gauss).

It is a widely used effect in graphics software, typically to reduce image noise and reduce detail. The visual effect of this blurring technique is a smooth blur resembling that of viewing the image through a translucent screen, distinctly different from the bokeh effect produced by an out-of-focus lens or the shadow of an object under usual illumination.

Gaussian smoothing is also used as a pre-processing stage in computer vision algorithms in order to enhance image structures at different scales - see scale space representation and scale space implementation.

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How do I gaussian blur an image without using any in-built gaussian functions?

I want to blur my image using the native Gaussian blur formula. I read the Wikipedia article, but I am not sure how to implement this. How do I use the formula to decide weights? I do not want to use any built in functions like what MATLAB has
Moeb
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How to calculate a Gaussian kernel matrix efficiently in numpy?

def GaussianMatrix(X,sigma): row,col=X.shape GassMatrix=np.zeros(shape=(row,row)) X=np.asarray(X) i=0 for v_i in X: j=0 for v_j in X: GassMatrix[i,j]=Gaussian(v_i.T,v_j.T,sigma) j+=1 …
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CSS-only Acrylic Material from Fluent Design System

With the advent of Microsoft's Fluent Design System and the propagation of the new Acrylic Material around the Windows ecosystem, I thought it would be great to use it in some Web layouts. Acoording to the spec, the composition of an acrylic layer…
Erick Petrucelli
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ImageMagick: Looking for a fast way to blur an image

I am searching for a faster way to blur an image than to use the GaussianBlur. The solution I am looking for can be a command line solution, but I prefer code in perl notation. Actually, we use the Perl image magick API to blur images: # $image is…
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Depth of Field: combining a point shader with a blur shader (Processing 3)

I would like to display thousands of points on a 3D canvas (in Processing) with a Depth of Field effect. More specifically, I would like to use a z-buffer (depth buffering) to adjust the level of blur of a point based on its distance from the…
solub
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How to define radius for blur with Python Pillow?

I'm trying to blur an image with Pillow, using the ImageFilter as follows: from PIL import ImageFilter blurred_image = im.filter(ImageFilter.BLUR) This works fine, except that it has a set radius which is way too small for me. I want to blur the…
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Why is Gaussian Filter different between cv2 and skimage?

I've got an image that I apply a Gaussian Blur to using both cv2.GaussianBlur and skimage.gaussian_filter libraries, but I get significantly different results. I'm curious as to why, and what can be done to make skimage look more like cv2. I know…
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How to get blur effect similar to Apple maps status bar?

I'm working on a map based iOS 11 application and want to make the status bar blurred exactly like it appears in the Apple maps. This is how it looks on the Maps app: Currently, I'm using UIVisualEffectView to replicate this effect. Here's my…
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Replace a chain of image blurs with one blur

In this question I asked how to implement a chain of blurs in one single step. Then I found out from the gaussian blur page of Wikipedia that: Applying multiple, successive gaussian blurs to an image has the same effect as applying a single,…
justHelloWorld
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Blurring a Rect within a screenshot

I'm developing an Android app which uses a background Service to programmatically capture a screenshot of whatever is on the screen currently. I obtain the screenshot as a Bitmap. Next, I successfully imported OpenCV into my Android project. What I…
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Fast Gaussian blur at pause

In cocos2d-x I need to implement fast gaussian blur and here is how it should looks like( I just found some game on the App Store with already done such blur, in unity): So, it's nice fadeIn-fadeOut blur when user pauses the game. GPUImage already…
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Correct implementation of Gaussian blur via FFT

I have read a lot of questions on SO about Gaussian blur and FFT, but there aren't answer how to implement steps of it (but there are comments like "it's your homework"). I want to know, how to properly pad the kernel and use FFT and IFFT on kernel…
Guy Fawkes
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Implementing a 3D gaussian blur using separable 2D convolutions in pytorch

I'm trying to implement a gaussian-like blurring of a 3D volume in pytorch. I can do a 2D blur of a 2D image by convolving with a 2D gaussian kernel easy enough, and the same approach seems to work for 3D with a 3D gaussian kernel. However, it is…
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Where is OpenCV's getGaussianKernel method's formula for sigma coming from?

I noticed that in the OpenCV documentation for getGaussianKernel, sigma is calculated using this formula: sigma = 0.3*((ksize-1)*0.5 - 1) + 0.8 Where is this formula coming from? Is this just some approximation that the OpenCV authors came up…
Shisui
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how do I implement Gaussian blurring layer in Keras?

I have an autoencoder and I need to add a Gaussian noise layer after my output. I need a custom layer to do this, but I really do not know how to produce it, I need to produce it using tensors. what should I do if I want to implement the above…
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