Questions tagged [gaussian-blur]
21 questions
51
votes
4 answers
How is Gaussian Blur Implemented?
I've read that blur is done in real time graphics by doing it on one axis and then the other.
I've done a bit of convolution in 1D in the past but I am not super comfortable with it, nor know what to convolve in this case exactly.
Can anyone explain…
Alan Wolfe
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Is doing multiple Gaussian blurs the same as doing one larger blur?
To make Gaussian blurring a 2d image faster, I know that you can do one axis and then the other.
I'm wondering though, if I did two Gaussian blurs of size $N$, would that be the same mathematically as doing one Gaussian blur of size $2N$?
Alan Wolfe
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Why do multiple Gaussian Blurs?
Applying multiple Gaussian blurs can result in an effect that is equivalent to a stronger Gaussian blur.
For instance this question says that: Is doing multiple Gaussian blurs the same as doing one larger blur?
Wikipedia also says it, but says that…
Alan Wolfe
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10
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1 answer
Gaussian blurring a function defined over a surface mesh
I have a scalar function defined over the vertices of a surface mesh. I want to compute an approximate (and generalized, I suppose) "Gaussian blur/convolution" of this function over the surface.
I can imagine for each vertex, taking an average of…
Museful
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2 answers
Bokeh from depth map
How do I generate bokeh that simulates shallow depth of field given a perfect depth map?
Here's what I tried:
Generated a sample scene using blender and corresponding depth map
Using Python, generated what sigma (standard deviation) to use at…
Saravanabalagi Ramachandran
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5
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2 answers
Will the gaussian kernels in this fragment shader be computed for every fragment?
I am running this fragment shader on every pixel on screen. I am trying to make it as efficient as possible. BTW I am running open gl es 2.0.
The code segment below is only a sample from the code, there are about 56 different calls to Gaussian()…
J.Doe
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5
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1 answer
Where are the highlight definitions inside of my shader?
I have a pretty good glow shader going now thanks to some tips from people here.
However there are a few things that bother me that could maybe be better.
#1 Definition of the particles
A lot of times if the particles are moving a lot it just looks…
J.Doe
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5
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1 answer
How does directional Gaussian blurring work?
In image editing software, you often have the ability to do a directional blur where you can choose and angle and a magnitude of a blur.
How does this actually work in practice with Gaussian blurring?
I could see possibly doing something like making…
Alan Wolfe
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5
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1 answer
Different types of Gaussian blur?
The Gimp has two different options in how you can perform Gaussian blur: "IIR" and "RLE". What's the difference between them?
Mark
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Texture prefiltering for Linearly Transformed Cosines
I'm implementing Real-Time Polygonal-Light Shading with Linearly Transformed Cosines from Siggraph 2016.
I'm stuck on the texture prefiltering (section 5.3).
As I understand they use Gaussian Blur on the texture, but clamp and normalize kernel to…
Derag
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Does a gaussian blur based bloom/glow shader require gamma correction? Any other tips?
Hello I have a simple application with some bright 2d mono-color shapes I am hoping to make appear emissive with a nice glow around them. To do that I am producing multiple gaussian blurs of varying kernels and resolutions and adding them all…
J.Doe
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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,…
user6321
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3
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1 answer
How can I implement a complex sinusoidal function?
The following is the 2d complex sinusoidal function,
$u_0$ and $v_0$ represent Fundamental Frequencies in $X$ and $Y$ directions respectively.
How can I represent $j$ (imaginary number)?
Edit:
here is my use-case: ... ... I need to implement…
user464
3
votes
1 answer
Plotting pbrt-v3 Gaussian filter
I want to plot the Gaussian filter of pbrt-v4 with a radius $(100,100)$ and a standard deviation ($\sigma$) of $0.5$.
I would expect something like this:
When I plot the pbrt-v4 Gaussian filter with radius $(100,100)$ and $\sigma=0.5$ I get:
Is…
Vertexwahn
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How does this app pull off fast, high radius HDR
I am in awe at this app I just found. It was actually one of the first things I installed when I first bought my iPad 2 but now they have updated it to add an HDR effect.
I have never seen a real-time glow effect that looked quite this amazing. I…
J.Doe
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