Questions tagged [digital-image-processing]
The digital-image-processing tag has no usage guidance.
20
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Minimum spanning tree between blobs
We have a binary raster image in which we consider the white blobs (connected components). We define a distance between two blobs to be the length of the shortest path between any two respective ...
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1
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42
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How to show invariance under additive and multiplicative illumination changes
The task is to "Show that the transformation f -> ((ln fx)x, (ln fy)y) is invariant under additive and multiplicative illumination changes."
From my lecture notes, for ((ln f)x, (ln f)y), ...
1
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1
answer
35
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Good Practice : Which VAE latent variable to use in dimensionality reduction
I'm trying to use a VAE (CNN-VAE to be exact) to reduce the dimension of some images I have in a dataset.
I successfully trained my VAE, but now I'm not sure of the latent variable to return.
Should I ...
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0
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24
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What is "energy" in computer vision
I keep seeing the term "energy" used in computer vision literature, specifically when speaking about Image Segmentation. For example on this page on Graph-Cut.
I'm just wondering if someone ...
3
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1
answer
66
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What is the time complexity of determining maximal overlaps between bitmap images?
Given two bitmap images (two arbitrarily sized two-dimensional matrices of integer values ranging from 0 to some maximum number), I want to determine their maximum overlaps.
An overlap is a relative ...
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2
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115
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Which algorithm is most suitable for comparing two images to find differences?
I have two images of two objects that are suppose to be exactly the same.
I use one for reference and one as my model.
I want to find an algorithm that will help me find on which areas these images ...
0
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1
answer
42
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2D fourier transform
I an new to image processing and I have some questions I want to understand:
What is the meaning of the imaginary and real part of the 2d fourier transform?
What can it tell me about the image it ...
1
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1
answer
44
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How can you apply dynamic connectivity problem to digital photos?
I started learning DSA recently and I came across the Dynamic Connectivity Problem. One of the listed real-world applications of the Dynamic Connectivity Problem is "pixels in digital photos.&...
0
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1
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353
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How many unique Huffman codes can you make. Image I has size 256x256 and has pixels of values 50,100 and 200
Let I (M x N) be an image made only of 3 pixels, how many unique Huffman code can you make (example: Image I has size 256x256, and has pixels of values 50,100 and 200).
If someone can help me how to ...
2
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2
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41
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What is an algorithm to do this binary image segmantation task?
What I need to do is go from a binary image like this:
to a segmented structure like this:
because I have a program that operates on those separated line contours after.
As you see, those contours ...
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2
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786
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What is the best way to compare two images for similarity if the brightness of the second image was changed?
I calculate similarity percent between two images. Another image is the same with changed brightness. I've already tried comparing by pixel (euclidean distance for grayscale and 0/1 values), comparing ...
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21
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point of view of each pixel with regard to the whole image
I am looking for a technique or an algorithm that outputs a unique number/vector for each pixel of the image. I want to give the pixel a perspective so the neighboring pixels have more visibility and ...
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0
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38
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Would a five color display have higher image quality than an RGB display?
We have five types of photo receptors in the eyes but computer color systems just use the three red, green and blue.
Three could be motivated if rod and melanopsin sensations are just linear ...
1
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1
answer
487
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If each pixel contains the channels for the 3 primary colours, why can a 1-bit picture only be presented in white and black?
I'm an igsce student. I'm taking computer science as an OL subject this year.
Pixels are the small squares which make an image. Inside each pixel there are 3 channels: one for blue, one for green, one ...
3
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101
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Algorithm to count number of overlapping rectangles of the same colour?
Say you have a grid of pixels. And there are 20 overlapping red rectangles on a blue background.
I want to find an algorithm to count the minimum number of rectangles that are needed to form the image....
3
votes
2
answers
101
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Matching superimposed image
We are given two grayscale images, one of which contains a large, mostly contiguous patch from the other one. The patch can be altered with noise, its levels may be stretched, etc.
Here's an example
...
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1
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304
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A pretrained model for mathematical equations characters detection
I am working on a project to convert equations to LaTeX code. After segmenting out the characters, I got stuck on the detection part and was looking for some pre-trained model that could detect ...
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I don't understand formula meaning of computer vision Paper
I am master degree student at Computer Science Department.
I started master degree at this year.
Now I'm reading two papers about computer vision.
Actually before time I didn't have experience about ...
0
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1
answer
397
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Greyscale image to binary image conversion using operations on pixel
Previously, I tried convert a color image into a greyscale image by using pixel values of an image from a simple formula :-
Grey = 0.3*Red + 0.58*Green + 0.11*Blue
...
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2
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68
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Transformation Function: Gonzalez and Woods
I have been reading Image Processing from Gonzalez and Woods and in the chapter Image Transformation I have come across this equation
$$
T \left(u, v\right)
=
\sum_{x=0}^{M-1}
{
\sum_{y=0}^{N-1}
...