Fft

Uses fft to calculate the circular cross correlation of two periodic signal vectors.This is equivalent to xc(k)=sum(u1.*circshift(u2,k)), but much faster (on the order of 500 times faster for a 1024 point signal).The package also includes two examples. One checks the calculation against the...

findFFT returns fft amplitude and frequency vectors from input data, with options to return normal fft, zeropadded fft, windowed fft, or both windowed and zeropadded to remove spectral leakage.IN data - vector containing information to perform fft on '-sampFreq',## - inputs sampling frequency of...

The INTERPFT function does sinc interpolation by taking an FFT, padding its end with zeros, and then taking an IFFT. Essentially, INTERPFT resamples the signal after low-pass filtering it.Instead of putting all zero padding at the FFT *ends*, that padding can be split so that some are at the...


Platforms: Matlab

This routine computes the fft of the input signal and removes power at the annual (or any specified frequency) by replacing the power at that frequency with the average of terms on both sides; this is done in the sine and cosine terms so as to average the power and the phase.


Platforms: Matlab

THIS FUNCTION PLOTS FFT OF THE SIGNAL INPUT TO THE FUNCTION ISuserfft(input, sampling frequency, waveform, psd) input -> Input waveform sampling frequency -> Sampling frequency waveform -> 'real' refers to real baseband signals plots only half the fft output -> 'complex' refers to complex...


Platforms: Matlab

Compute the discrete Fourier transform at specified frequencies, not using fft.Why one may need this?(1) MATLAB fft function computes the amplitude of signals only (no phase).(2) Once having the recorded time-series data, one often uses fft to do the spectral analysis. However, the frequency set...


Platforms: Matlab

This function convolves two very large vectors very quickly. Enormous gains in speed are due to the use of two fft's and an ifft. To find out how to use this program, put it in you 'work' folder and type "help fconv".


Platforms: Matlab

Many image processing applications require an extensive usage of FFT2 routine (or, in the most general case, a N-dimensional FFT) of matrices having the same dimensions. In these cases MATLAB FFT2 can result extremely inefficient. In general the execution time can be significantly reduced by...


Platforms: Matlab

Performs N-D FFT interpolation on any data for which fftn works. Will upsample by zero-filling, downsample by truncating high frequencies, or combine both up- and downsampling by dimension to allow arbitrary reshaping.


Platforms: Matlab

The routine display the outputs of intermediate butterfly stages


Platforms: Matlab

This matlab scprit calculates fractal dimension and intercept of a 3D volume along each redial line using Fourier analytical technique. Directionally averaged fractal dimension, intercept and Hedgehog plots of fractal dimension and intercept of each direction are given.


Platforms: Matlab

FDSURFFT computes fractal dimension (slope) of surface image im and draw rose plots of slope and intercept.


Platforms: Matlab

Spectrum scope makes it easy to compute and display the fft of a live signal. You feed it your time series data, and it does the rest. It works very nicely with the Timer objects introduced in R13, and with Analoginput objects (from the Data Acquisition Toolbox).Here's a simple example, assuming...


Platforms: Matlab

[G GWINLEN] = genGaborKernelF( MU,NU,sigma,scaleXY,imgSz )GIMG = GABORCONV(IMG,G,GWINLEN)Extract the texture feature using Gabor filter/wavelet. You should first generate cell array G, which is a set of kernels in freq domain, then pass G and the image to the function GABORCONV.


Platforms: Matlab

if you know the required length of your dft,you can use use this...


Platforms: Matlab

Computes by using the FFT (fast Fourier transform) algorithm the covolution of two discrete sequences.


Platforms: Matlab

This package provides implementations of several spectral (FFT,DCT)saliency algorithms for images.There are several methods (multichannel_method) to calculate themultichannel saliency:'fft': by default the same as 'fft:whitening''fft:whitening' Uses spectral whitening to calculate the saliency of...


Platforms: Matlab

When producing a spectrum with fft.m there is no build-in m-file to find the corresponding y-axis. Example; if you want to plot the real Fourier coefficients of a signal (y) with corresponding time (t), write 'plot(freqspace(t),real(fft(y)))'. Created while finding derivatives in the Fourier...


Platforms: Matlab

This is a simple FFT based beam propagation method for potential-free 1+1+1D Schrodinger equation. The software if flexible and allows to introduce high-order derivatives in the term (very handful if is needed to include dispersion effects). For example, if one desires to solve an equation in the...


Platforms: Matlab

Achieve a 3D convolution in the fourrier domain.% convolution3D_FFTdomain - Performs a fast 3D convolution between volumes using mutliplication in the Fourrier spaceSyntax: [outVol] = convolutionInFFTdomain(inVol,inKer)Inputs: inVol - input volume inKer - input kernel inMsg - display succes...


Platforms: Matlab