The image-processing tag has no wiki summary.
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DFT/FFT: What did N stand for again? [migrated]
So if I have an image of the size: 1920×1080 and I want to apply a convolution filter of 3x3. What is N in this case?
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Explanation of LidarBoost Algorithm?
I am trying to understand the LidarBoost algorithm as explained in this paper (PDF warning). My apologies if this isn't the appropriate exchange; I've posted in DSP, but I didn't get a response there, ...
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Speedup prediction of rotating mask filter
I am trying to do the speed up analysis of the rotating mask filter (section 4.2.3).
Let $N^2$ be the pixels in the image and let $m^2$ be the neighborhood of a given pixel, what I have for my ...
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1answer
70 views
Flipping the kernel in 2D convolution?
SEE: http://www.songho.ca/dsp/convolution/convolution2d_example.html
"First, flip the kernel, which is the shaded box, in both horizontal and vertical direction"
Why do we need to flip the kernel in ...
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1answer
82 views
Mathmatical way to represent a image kernel?
How to represent the calculation in this image ( http://i.stack.imgur.com/vpbuy.gif ) mathmatically?
For example: With the discrete convolution
$(f * g)[n]\ \stackrel{\mathrm{def}}{=}\ ...
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How does the Trimulus sensitivity functions relate to the luminosity function?
In colorimetry, the irradiance spectrum is weighted with the luminosity function to obtain the perceived luminosity, and the tristimulus sensitivity functions to obtain the perceived ...
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1answer
64 views
How do convolution matrices work?
How do those matrices work? Do I need to multiple every single pixel? How about the upperleft, upperright, bottomleft and bottomleft pixels where there's no surrounding pixel? And does the matrix work ...
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1answer
387 views
Second order directional derivative in image processing
it is all about valley detection in image processing.
I would like to find, for a given pixel, direction for higher second order derivative. I am not quite sure what discrete mask/filter I can use to ...
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2answers
212 views
Algorithmically selecting colors that will contrast with their background
I am trying to write an implementation of a color quantization algorithm in order to find an image's dominant colors (say 5) and then find contrasting colors based on the colors found in the image.
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1answer
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What does “missing-wedge corrected” mean?
For identification of macromolecular complexes in cryoelectron tomo-
grams covering cytoplasmic regions, we used a combination of
subtomogram averaging and classification. In a first step, ...
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1answer
266 views
Optimal transport warping implementation in Matlab
I am implementing the paper "Optimal Mass Transport for Registration and Warping", my goal being to put it online as I just cannot find any eulerian mass transportation code online and this would be ...
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2answers
182 views
Trace An Isoline of an Expensive 2D Function
I have a problem similar in formulation to this post, with a few notable differences:
What simple methods are there for adaptively sampling a 2D function?
Like in that post:
I have a $f(x,y)$ and ...
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118 views
Texture analysis methods modern survey paper
I want to study the methods of analyzing textured images. So i searched google scholor but only found very old papers
statistical and structural approaches to texture 1979 haralick
Image Texture ...
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3answers
387 views
Computational Complexity of Image Segmentation algorithms
I have a question. I need to calculate the computational complexity of image segmentation algorithms. Can anyone please help me?
For example, I have a screen-size picture with white background ...
