Questions tagged [image-processing]
The image-processing tag has no usage guidance.
266
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What is a good appropriate algorithm for localization for images?
Assume that you have an image that you going to classify its class ID.
One good option is to use interest points e.g FAST that can find coners/edges inside an image.
From these points you could ...
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Detecting thin lines in binary images
I want to find areas in a binary image that correspond to long and thin curves. In the example below, structures thinner than 3 pixels but longer than 20 pixels are highlighted. Observe that the ...
user16034
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3
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Given two sets of coordinates, find out neighboring ones
I have two sets of 2-dimensional coordinates on an integer grid, $A$ and $B$
$A = \{(x_{A1},y_{A1}), (x_{A2}, y_{A2}), (x_{A3}, y_{A3}), \dots\}$
$B = \{(x_{B1},y_{B1}), (x_{B2}, y_{B2}), (x_{B3}, y_{...
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Determining all pixels of a specific color directly bordering on another color
I need a data structure/algorithm to efficiently retrieve borders and update changes.
There may be many (unconnected) regions of the same color. The shape of regions changes frequently over time and ...
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Does flipping the kernel in image processing only help maintain mathematical symmetry?
So I've been really confused about the act of flipping a kernel in image processing. Is there any intuitive way to think about it or does it only help computing efficiently and maintain the ...
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Details about KNN based background segmentation
I build a python script which uses OpenCV implementation of KNN Backgroud Segmentation/Remover.
I know the basics of how KNN works, but not how the background segmentation works.
For the MOG algorithm ...
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How can I find a Stable Diffusion program?
Well, I know that I'm going to ask too much.
So, I really want to ask you a totally (powerful (!)) free completely off-line code to generate prompt-based images like midjourney. I want to run with my ...
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Calculating the Correct Translation and Scaling Transformations for Segmentation Polygons
I have an image with a list of segmentation polygons. Getting the bounding box with the polygons is easy enough. I used the bounding box to crop out the objects of interest.
Now, I want to scale the ...
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Finding whether a point lies on the boundary of an geometrical object or not?
Suppose I have the mesh of an geometrical object (Interval in 1d, Region in 2d, Volume in 3d). How can I find out whether a point lies on its boundary or not?
I am looking for algorithms with ...
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Count the number of lines in binary image
Consider I have the following binary image (each pixel is either 0 or 255). How to count the number of lines (they could be straight or a little curvy). For example, in the picture, there are six ...
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Interpreting results of Sobel Edge Detection
I am implementing A No-Reference Perceptual Blur Metric paper.
Somewhere in the prep steps they mention the use of vertical Sobel filter for finding vertical edges.
The algorithm is summarized in Fig....
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Algorithm to find best alignment of one curve onto another
So I've boiled a certain problem I have down to the point where I have two images of (approximately) the same scale. One which contains a closed curve, and one which is a partial curve. I want to ...
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What is the best way to predict a continuous score based on image characteristics(pixels)?
I have a dataset with 9912 images, what is the best way to train them based on the pixels and features of the images to be able to predict a continuous target ranging from 1 to 100? The goal is to ...
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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 ...
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Fast Algorithm To Compute Gradient Of Gaussian Blur
what is the fastest algorithm to compute the gradient of the Gaussian blur of a (grayscale) image, with a blur radius of around 100 pixels, where smoothness of the result is important to me, i.e. no ...
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preprocessing or real time for magnification of portions of video
Im new at CS and would like to gather preliminary information to approach an interactive art project.
I want to construct a grid of videos - think about a matrix M = m x n where Mi,j is a video that ...
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RGB synthesis in pixels in a computer
A pixel is contained of 3 ranges of RGB color synthesis to add colors into a tiny-square small box, as I learned (correct me if I am wrong). But, through these 3 colors admixture can we create any ...
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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 ...
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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 ...
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134
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Computational complexity of median filter in image processing
I found this paper http://nomis80.org/ctmf.pdf, that describes an efficient algorithm for applying a median filter to an image. Though this works for non-HDR images, I am not sure how well it scales ...
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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 ...
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Predicting continuous variables using image and text input to neural network
I am looking to create a neural network architecture that takes two kinds of inputs: image and text, and outputs a predicted continuous variable. More specifically, I will have multiple images of a ...
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258
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How many pixels support each neuron in multi-layer CNN?
I'm studying for a computer vision module and I'm on the deep learning topic, in one past paper we have the following question:
Given that a convolutional neural network has five convolution layers (...
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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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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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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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433
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Inverting an image, as a matrix
I am curious about something pretty simple, though I have never heard, read and more sadly seen any example of it.
Take any image, represent it as a matrix, invert the matrix (assuming the inverse ...
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Which pretrained model will be best for my dataset?
I am trying to build a classification algorithm having 28 classes. These classes consists of Logo of companies like adidas , Nike etc. I have very low dataset below than 100 images and greater than 70 ...
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What is a task type?
I have an unlabeled dataset: 500 X-rays of seeds in husk. In each image there are different number of seeds, for instance, from $10$ to $50$.
A seed has some features. The main features are a seeds' ...
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Affine transformations for twisting and pinching
In image processing we can use affine transformations for translation, rotation, shear and scaling of pixels. But what kind of transformations are used for twisting and pinching of image pixels? Or ...
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Inability to understand local fourier analysis in the given link
https://www.researchgate.net/publication/235662494_On_separating_overlapped_fingerprints
[Paper name-"On separating overlapped fingerprint", author-Fanglin Chen,Jianjiang Feng,Jie Zhou]
I ...
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approximate line segments from array of unsorted points
The polygon above is actually a collection of a lot of black points closely packed together. I want to approximate these black points as straight line segments. The black points are not sorted in any ...
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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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How are epipolar lines useful in computer vision?
Why do use epipolar lines and what are it's benefits in computer vision ?I am unable to find the uses of epiploar lines and how they are helpful although i am aware of epiploar geometry concepts.
I ...
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Performing semantic segmentation on images on word documents
At the moment, I'm making a comparative analysis between two different neural networks for a class. The problem they are both trying to solve is detecting tables on documents. Below is an example of ...
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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 ...
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What is an algorithm to find the largest rectangle of white space in an image?
Take an image, (the Google home page) is a good example.
I want an algorithm to find the largest white rectangle in this image. That is to say, the largest rectangle that would fit in an area of ...
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Applying SVD compression to integral point images
Suppose that we have an $m\times n$ matrix $A$ of rank $n$, whose entries are 8-bit unsigned integers obtained from a grayscale image. Now we want to apply SVD to $A$ and to use the first $k$ singular ...
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What is the best algorithm for detecting the texture of a person's clothes in real-time for a mobile robot?
I am working on the human following robot. the robot extracts a feature of clothes's texture and distinguishes between the people that they stand up in front of the robot. So, the robot needs that it ...
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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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443
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An algorithm to find the closest match between 2 arrays of RGB pixel tuples
So I'm looking for a bit of an abstract algorithm and I'd appreciate any references to read up on. This is a bit tough to explain but I'll try my best.
Suppose we have 2 arrays of ...
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Image/Video deblurring
I am currently working on an algorithm that will help to improve shaken blurry images. I know there are plenty of them, such as deconvolution, that is pretty useful though I don't really know how to "...
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Why HOG angular bins have values between 0 and 180 degrees?
I have learned that HOG angular bins have values from 0 to 180 since the algorithm uses unsigned gradients. I am failing to understand why.
As far as I know gradient orientation is calculated as
<...
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Image classification with zero data
Given an image of a biology diagram, I would like to classify the diagram into these 4 categories:
Plant
Animal
Cell
Anatomy
However, I don't have any training data. I would like to avoid the ...
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Image segmentation of a high resolution 2D binary image into clusters, threads and points
I use python3 script to find out the area proportion of pixel clusters, threads and points in my image. They are originally 8-bit greyscale TIFF images with a resolution of 2048x2168 pixels. I have ...
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Gaussian noise: Image Processing
As we all know, Gaussian Noise follows Gaussian or Normal distribution, and that distribution follows a $BELL$ $CURVE$.
As we can see that most of the values are centered around the mean.
Now ...
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"higher intensity" and "high signal intensity" in images
I'm newbie in Computer Vision and image processing.
I'm reading the article "Automated White Matter Hyperintensity Detection in Multiple Sclerosis Using 3D T2 FLAIR" and it said:
2.2.4. WMH ...
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What is f(x,y) in Digital Image Processing?
I am a novice in Digital Image Processing, and while reading the book of DIP by Gonzalez and Woods, I find that they have represented digital image as $f(x,y)$ but nowhere it is mentioned what is $x$ ...
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Hausdorff distance between two binary images according to distance maps
I want to compute the Hausdorff distance between two (very large) binary images X and Y, which is:
$$H(X,Y) = \max\left\{\,h(X,Y), h(Y,X)\right\}\!$$
with
$$h(X,Y) = \sup_{x \in X} \inf_{y \in Y} d(...
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Tapered Quantization
In Gonzalez et al it is mentioned that Tapered Quantization is
I am unable to figure this thing out. I have searched the whole internet, but nothing of the same appears. I need a help in ...
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