Questions tagged [image-restoration]
The image-restoration tag has no usage guidance.
31
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Using an experimental PSF to perform a deconvolution
I have an experimental PSF (point spread function) of an optical system for remote sensing images.
However, it is asymmetrical and has some sidelobes as below.
And I want to perform deconvolution to ...
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2
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118
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How to produce self-adjoint filters using Gaussian and motion blur in Matlab?
I am trying to write a Matlab code to produce motion and Gaussian blur. Here is my code:
...
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249
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Problem with running BM3D implementation in Python
I found about one of the BM3D implementation in Python through this post and tried to use the same, however, I don't see any difference after using the algorithm.
Here is a small snippet of my code,
<...
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57
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Edge / Pixel Type (Homogenous, Edge, Texture) Classification as Part of an Image Denoising Procedure
For most noise reduction algorithm, the same process is applied to every pixel no matter
the pixel belongs to one of three types of pixels such as homogeneous regions, edges or textures.
Different ...
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56
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bias-variance trade-off in image denoising
I am reading the paper A Bias-Variance Approach for the Nonlocal Means.
One sentence from the paper is as follow:
To discuss the tuning of parameters of the NLM, we interpret this
choice as a bias-...
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2
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586
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Metric for image sharpness?
Suppose I have a blurry image: a photo convolved with a gaussian blur kernel of unknown sigma. I would want to deconvolve the blurry image using several gaussian kernels (with different sigmas). Is ...
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4
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732
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Universal Bases (Dictionary) for Image Compression
I am a physics graduate student working on a data compression problem. I have been reading Prof. Steven L. Brunton's book on data driven science and engineering.
I am fascinated to the concept of ...
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92
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Basic Wiener application
I'm trying to filter this $g(x,y)$ WGN added
image
My Wiener filter is:
$$H(u,v) = \frac{P_{f}}{P_{f}+P_{n}}$$
Where the image power spectral density $P_{x}$ is estimated as $\frac{|X(u,v|^{2}}{N^{2}}$...
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83
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How to enhance thermogram image in grayscale?
I'm trying to do some image processing to improve the image below but I'm having some trouble. I already tried to do histogram equalization followed by laplace sharpening, I tried to implement a ...
3
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1
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86
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Can a linear reconstruction in compressive sensing perform well?
I am trying to implement compressive sensing for grayscale 2D images, then reconstructing them using a multi-layer perceptron(MLP). It seems to perform well no matter how many layers I add or remove, ...
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How can I compute the result of the magnitude of edges of an image?
I have a random image with 11x11 pixels. In the center of the image is a square of 5x5 pixels. The gray level of the background is 0 and the gray level of the square is 50. How can I compute the ...
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Image Restoration by Solving Constrained Least squares in Frequency Domain (Frequency Domain Filtering)
I am trying to implement the constrained least squares filtering as described in Rafael C. Gonzalez, Richard E. Woods - Digital Image Processing 3rd Edition Section 5.9. The equation (...
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195
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Having converted a grayscale image to binary using `im2bw()`, is the converse operation possible?
I have converted a gray-scale image to binary using im2bw() now i wanna do the opposite. How can I do that in MATLAB?
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110
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Comparision between SSIM and MAD Image Quality Assessment Algorithms
I have been working with Most Apparent Distortion(MAD) tool to evaluate the quality of images. I have read a paper that compares SSIM, PSNR, FSIM, etc. with MAD. I am uncertain about some calculations ...
- 113
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Image Restoration and Standard Forms of Second Order Cone Programming (SOCP)
I'm studying the application of SOCP methods in Image restoration And I want to understand the difference between the two formulas of SOCP and how they are related.
Standard form (1) :
min $f^{t}x $
...
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1
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131
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Measure how Straight/Smooth the Borders are Rendered in an Image
I have two images:
I want to measure how straight/smooth the text borders are rendered.
First image is rendered perfectly straight, so it deserves a quality measure ...
- 127
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440
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Proximal Gradient Method (PGM) for a Function Model with More than 2 Functions (Sum of Functions)
I am currently working in signal reconstruction. I am trying to develop an algorithm where the user can plug any constraint to the main objective function (let's say chi2, least squares). I was trying ...
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1
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144
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Removing striped noise from an image
I was just wondering if anyone could explain to me the approach one would take to removing striped noise from the fourier domain of an image. I was reading an article about MRI image from 1 just ...
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43
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Elimination of image blurring using noise model restoration techniques
How can the blurring be eliminated from image using the noise model restoration process techniques?
To my knowledge the answer must be filter.If yes,then which filter is used?
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205
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Converting very short "motionless" video frames to single, better-resolved, images
I made a mistake with my newly bought compact camera, before a trip to Japan. Instead of taking single pictures, I ended up with a few short "MP4" video files (1 second, 2-3 frames). I could ...
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Switching camera angle based on several images
Given a number (3 or 4) of different images of a given subject from different angles, how do I interpolate to an angle that isn't available on any of the photos?
What is this technique called and is ...
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2
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Is It Possible to Reconstruct the Original Image from Laplacian Pyramid?
In our computer vision course, my professor said we can reconstruct the original image from the Laplacian pyramid. It just feels to me that information is lost after doing subsampling and upsampling.
...
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Is SSIM a measure of mutual information?
As i have seen contradictory information online: is the quality measure SSIM between two images (one base-line, one distorted) directly correlated to the mutual information between the two. One one ...
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103
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Histogram of Gradient
I was calculating which would be faster in computation, Inverse Fast Fourier Transform or Histogram Of Gradient but I am unable to calculate its running time.
What would be the running time of ...
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633
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Removing bright lights from image using Matlab
I want to remove a bright spot in an image. This is the image I used:
and this is the Matlab code I wrote:
...
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0
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201
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How to remove artefacts from this image?
There is some vertical banding near the tree trunks in the following image.
Is there a way remove this type of artefact, preferably using Mathematica?
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How is WSNR (weighted signal to noise ratio) defined?
I'm studying about comparison between images to determine quality. I've learned about MSE, SNR and PSNR, and now I'm trying to understand WSNR, which I assume is similar to SNR but with weights.
I ...
3
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1
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391
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Best (Perceptually / Objectively) Super Resolution Methods Out There?
I'm curious about the advances in the area of image super-resolution (SR) that have given the best results to date, both perceptually (visually pleasing) and objectively (e.g. PSNR, SSIM criterias). I'...
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Formula for 2D Image Filter for Scratch Detection
Consider Multidirectional Scratch Detection and Restoration in Digitized Old Images Research Paper.
In section 4.1 (Preprocessing), they gave us a formula of the kernel,
$$ H(u, v) = \frac{1}{1+0....
user18425
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What are Local and Global Inpainting Techniques in Image Processing?
Is Diffusion-based inpaiting Local or Global?
Is Pixel-based inpaiting Local or Global?
Is Patch-based inpaiting Local or Global?
Can Local-diffusion be used inside Patch-based in-painting problems of ...
user18425
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5
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How to Remove a Glare / Clipped Brightness from an Image?
I have an image
Is there any way of removing the bright white spots ? Please help thanks
Edit:
After operating with gaussian and then displaying using imagesc get the following output which ...
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