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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gaussian blur in webgl error

I am trying to write a simple gaussian blur shader in webgl. i have searched a lot about this and i think i understand the idea behind it. given this 3X3 kernel .how can i apply it to my vertex shader? Here is my current output [ 0.0625 0.125 …
anekix
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Change height of an element on scroll

I am trying to increase the height of an element when a user scrolls on page. I have tried several methods, but for some reason I can't get it working. The idea is following. I would like to have a div which contains duplicated content of a div…
prius
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How do I subtract pixels from Gaussian, divide by Gaussian, and normalize in imagemagick

I know exactly what I want to do, and could do it with python, scipy, and PIL. I want to use imagemagick, since it is designed specifically for these actions. T is highest legal intensity (0, of course is lowest) Input image into temporary MPC…
jlettvin
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iOS 9.3 UIGraphicsImageRenderer showing nil any other option for this?

I'm want apply feather effect to the image when cropped but want i render the image using UIGraphicsImageRenderer the render is nil(iOS 9.3) is there any other option for rendering the image in iOS 9.3 This is my code: UIImage* Img =…
Mitesh Varu
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making a rotated DoG filter using filter2D

I have an assignment for a ComputerVision course I'm having trouble with. I need to filter out the yellow lines of the image below using a rotated DoG filter. As a first step I want to make a custom 2D gaussian kernel(with 2 different sigma's,…
Xilef
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How can I set the kernel of a Conv2d filter to be a Gaussian filter?

I have a 2d Gaussian filter h, and I have initialised a Conv2d filter with conv_filter = torch.nn.Conv2d(in_channels=1, out_channels=1, kernel_size=(sigma)) I attempted to set the weights with with torch.no_grad(): conv_filter.weight =…
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Why cv2.GaussianBlur modify max value?

Why cv2.GaussianBlur modify max value in this case? Here is example code: import numpy as np import cv2 mask = np.zeros((256, 256, 1), np.uint8) mask[128:, :] = 255 np.max(mask) 255 mask = cv2.GaussianBlur(mask, ksize=(15, 15), sigmaX=0,…
mrgloom
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Generated gaussian kernel saturates the image to white color with opencv in C++

I'm trying to implement a function that gives me the Gaussian kernel given a certain standard deviation and dimensions. The output of the function seems correct, but when I apply it using the cv::filter2D function the result I obtain is quite…
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Cairo blur surface

I can't figure this out , can you guys help a bit I have am original cairo surface srf and its context c now I am creating another surface shadow and superimposing it on previous one by cairo_t *cr = c; cairo_surface_t *shadow =…
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Gaussian filter for a one dimensional array

I want to apply a 1D Gaussian filter on a 1D array. For Python there are many libraries for this, but i did not find any for android. So i want to do it without a library. What is the best way to do this? Which is the right formula to do this? I…
Alex
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Why the brightness of the image got reduced after applying gaussian filter?

I just learned how to apply a gaussian filter from scratch to a Grayscale image in python from this blog: http://www.adeveloperdiary.com/data-science/computer-vision/applying-gaussian-smoothing-to-an-image-using-python-from-scratch/ Now I want to…
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Applying CIGaussianBlur to UIImage not working properly

I want a blur effect to UIImage as slider value changes. I am using the CIGaussianBlur filter to blur the image. The code is as follows func applyBlurFilter(aCIImage: CIImage, val: CGFloat) -> UIImage { let clampFilter = CIFilter(name:…
Krima Shah
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How to use different kernel shapes while blurring an image?

I want to use a fast blurring function like cv2.GaussianBlur() but it only allows for rectangular kernel shapes. Is there a way to use elliptic kernel shape? If any other blur function allows it, can you please suggest that function?
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Blur value decreasing in IOS 13 - filters.gaussianBlur.inputRadius

I’ve been struggling with a bug since I changed the version of Xcode 10.3 to 11 beta and iOS 12 to 13. This bug is related to UIVisualEffectView and the value of the blur changing while navigating through the App. Basically It’s a bank App where…
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How can I do a Selective Gaussian Blur on OpenCV?

I would like to make a noise reducition filter on OpenCV just like the Gimp's Selective Gaussian Blur: https://docs.gimp.org/en/plug-in-sel-gauss.html The filter compares each pixel with its surroundings and only blurs if the difference is lower the…
Pedro Serra
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