Questions tagged [fourier-transform]
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Doing spectral analysis in GLSL, how can I get FFT-level fidelity in my results?
I'm using GLSL to do spectral analysis of an input signal. I do the math to associate each pixel (in a single row) with a frequency, then use [The Goertzel Algorithm][1] to determine the contribution ...
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Is it possible to separate or split original images (or videos) from a blend image (or video)
The title says it all. Blended image or video contains multiple image or video blended on top of each other. I am looking for any software or tools that can separate the original images or videos.
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How to calculate spatial frequency of an image just in one direction?
FFT spectra is not what is needed; what I need is a histogram showing which frequencies are there in image in horizontal direction, and which one is dominant
Such spatial frequency is usually known ...
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Sub-pixel image registration using phase
Currently I'm trying to reproduce the result by the academic papers Sub-pixel Shift Estimation of Image based on the Least Squares Approximation in Phase Region by Fujimoto, Fujisawa and Ikehara (...
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Why is spherical harmonics used in low frequency graphics data instead of a spherical Fourier transform?
I'm curious why spherical harmonics are commonly used in real time graphics instead of a spherical Fourier transform.
I get that spherical harmonics are in a sort of frequency space (like FT is) so ...
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Image rotation using FFT
I'm not sure how practical this might be but is it possible to use Fast Fourier Transform to rotate a raster image?
To be honest, I never really understood FFT, but I saw it being used for JPEG, for ...
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How does a 2D Fourier Transform of an image work?
I understand how a 1D Fourier transform separates a signal into its component frequencies, but I'm having difficulty understanding how a 2D Fourier transform affects a 2D image.
From another question,...
