Questions tagged [image-processing]
The image-processing tag has no summary.
68 questions
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Why do images invert to create a perfect image (ie a pinhole camera)
This image has always confused me, and it seems to be the go to example when explaining why images are inverted when looking through a pinhole camera.
I understand that light travels in a straight ...
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What is the relation between image resolution and Cutoff from 2D FFT functions in frequency space?
This might be dumb, but unfortunately I need some urgent help about Cutoff from 2D FFT functions in frequency space.
I am writing my bachelor thesis, near DDL and cannot get a lot of help offline in ...
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How to decipher imaging method used in remote sensing images?
I am working on remote sensing for science olympiad (div c) and i am kind of lost on remote sensing image analysis. like how do i look at an image and know it was captured using infrared or microwave ...
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How do I finde the units of my temporal Fourier transform?
I am trying to extract harmonic motion from series of images. One approach ist to simply take the (discrete) fft:
tmp = fft(imageSeries, [], 3);
where imageSeries is a stack of black and white images ...
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What is the input of calculating signal noise ratio (SNR) and detective quantum efficiency (DQE) in estimation of imaging system?
In its definition, the signal noise ratio (SNR) is the ratio of the mean siganl to the standard deviation of the noise. However, for a given picture what is the noise? The detective quantum efficiency ...
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How to set mask size when apply inverse-FFT to the power spectrum of HAADF-STEM image?
Hello everyone, I want to characterize dislocation in my FIB sample using Titan electron transmission microscopy and I want to use FFT filter to process my HAADF-STEM image with DigitalMicrograph (...
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On a fundamental level, why is white balance in cameras even necessary?
When searching online about what the white balance setting in cameras does, you'll probably find an answer that goes something like this:
When taking a photo, the color of the lightsource might be ...
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What is meant by 2D fourier transform of an image?
I have some questions about this interesting concept I came across about 2D Fourier transform, please...
Firstly, the Fourier transform of a 1D signal (such as a sound recording) is as follows:
The ...
user315366
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Myopia far point virtual image
My textbook says that a diverging lens works by rendering the object a virtual image at the myopic eye’s far point. However, wouldn’t the eye then perceive an object farther than its far point at the ...
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Replica calculation in statistical mechanics
i am reading "Statistical physics of spin glasses and information processing an introduction - Nishimori Hidetoshi", chapter 6, page 119 on image restoration. I tried to understand what ...
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Is it possible to get a resolution that is better than what is given by the Rayleigh criterion?
I remember reading recently that it is possible to unblur a face that has been blurred by using a computer to process multiple images of the blurred face from different angles. This got me thinking, ...
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What is the theoretical limit for image sensors?
Telescopes are principaly limited by a diffraction-limit.
Does this limit affect the image sensor?
The Rubin Observatory LSST Camera, the biggest camera in the world with 3.2 gigapixels is having a ...
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Can an image formed by gravitational lensing be corrected for the inevitable aberration?
Carl Zeiss would not be impressed with your average gravitational lens. Compared with familar optical lenses that are generally used to form sharp undistorted images, gravitational lenses make quite a ...
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Calculate Modulation Transfer Function from Line Spread Function
I am trying to measure the MTF of a radiology imaging system from a set of CT scans of a phantom. The imaging system is primarily designed for stationary scans so the CT images were low in spatial ...
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Estimating the focus plane of camera via thin lens equation [closed]
I have a camera that outputs a JSON file for every image taken. In the JSON file, I can find camera-specific and also the photo-specific acquisition parameters used. The issue is I wish to estimate ...
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