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I am working in the field of digital image processing and currently i am reading this paper and I have two questions about it....
After applying a gaussian filter to a histogram, will the pixel values of the new histogram be changed or not?
And will the sum of pixels in new histogram be the same or not?
|
I am using an adaptive RLS adaptive filter for noise cancellation. My sampling freq. is 500 Hz, but I am interested in only frequencies of up to 60 Hz. I filter the input and the reference signal to the desired frequency range and then apply the adaptive filter. The adaptive filter does a good job at removing the noise... |
I have created a frequency domain image filter and would like to test it against some images where it is known that the frequencies only occur within a given band. Trouble is, I don't know how to go about creating such images.
I have though about making an image that consists of intensities varying about the x and y ax... |
My aim is to find cluster phonemes from a wav file. I would like to go through the following steps:
I am calculating spectrogram.
Calculate energy of each frame.
Cluster the frames using k-means clustering.
save the clustered frames as wav file.
Now I am in confusion, what should be the critarion to find the similari... |
I'm using cross-correlation to look for a Barker code in a BPSK signal. It occurred to me that if I send out a zero DC valued signal proceeding the barker code, it won't affect the correlation because a zero DC signal has zero correlation with any other signal.
This made me wonder if there's an alternative to cross-co... |
I am quite familiar with signal processing using Matlab. Now I am working in its open source alternative 'Scilab.' In Matlab, cconv() function is used to perform circular convolution between two sequences. I want to do circular convolution in Scilab. But I could not find an equivalent function for circular convolution ... |
I've been using F-K Filter, for a while, but I guess I never had good basic understanding about it Math. Someone asked me what is the cause of frequency wrap around in F-K Spectra plot ? I know it's because of aliasing. But if somebody please elaborate more on the cause of this wrap around? Simple Math explanation perh... |
This question is theoretical. Let's say you have three different highly compressed images of a same source image, each compressed with a different algorithm and thus "lossy" in different ways.
What would be the possible techniques to recover the best possible image, using the three different compressed versions ?
|
I've been trying to model some radio signal properties of wireless networks wrt its usefulness. For example, most WiFi network adapters would decrease their transmission rate if the overall quality of the signal is bad so as to avoid re-transmission, errors, etc.
What is the relationship of the received signal strength... |
Here is the problem. I have a 2D array of data, first column represents the time data and the second column represents the sinusoidal response data, based on the time data. I apply fft and I get my frequency (that I started with) in a specific bin as I expected and I find the amplitude and phase angle from that bin. No... |
I have asked the same question in stackoverflow ,https://stackoverflow.com/questions/17794772/steps-for-successful-image-recognition/17840975?noredirect=1#17840975, but since I am not getting considerable responses , I'm going to ask it again here .
In order to do successful image recognition what are the steps one ha... |
What I'm trying to do is, given some experimental data and it's (magnitude normalized to 1) FFT, match the FFT with one of say 1000 other (magnitude normalized to 1) FFT plots. Please note that the experimental/generated plots all have the same bin width/count.
Initially what I'm doing is taking the normalized cross co... |
I'm not sure if I'm on right place to ask a simple suggestion, so please be kind and don't downvote my question. I'm not asking someone to do it for me, I just need short guidance how should I proceed.
Currently, I'm writing a study of Blind source separation using eigenvalue decomposition. Since I'm not good at writin... |
I've read that OFDM normally uses a one-tap equalizer. It seems that a one-tap equalizer could only scale and delay a signal. Why is this useful?
I thought multipath was handled through the cyclic-prefix and by choosing a symbol width that is large compared to the delay spread. Why is an equalizer needed at all?
|
I'm currently using MATLAB's fdatool for filter design. Using that tool, I can easily design different kind of filters. For example, let's take a band-pass FIR filter with 10-40 Hz passband, and 5-10 Hz and 40-45 Hz transition bands. Usually, I design the filter with the selection "least-squares", which, if I understan... |
I've implemented a gaussian blur fragment shader in GLSL. I understand the main concepts behind all of it: convolution, separation of x and y using linearity, multiple passes to increase radius...
I still have a few questions though:
What's the relationship between sigma and radius?
I've read that sigma is equivalent ... |
As the title suggests , I'm looking for good books on medical imaging . It would be a great help if you can provide a link to the books website .
Thanks.
|
If I have a signal that has 740 samples, the sampling frequency is 1000 Hz, and I take an FFT of length 1024, are the frequencies I get now 0, fs/1024, 2*fs/1000, ..., 511*fs/1024? I mean, do I get this correctly: the frequency resolution does not depend on the number of samples I have, only FFT length and sampling fre... |
I have a thirty-second speech signal that was sampled at 44.1 kHz. Now, I would like to show what frequencies the speech has. However, I'm not sure what would be the best way to do that. It seems sometimes one calculates the absolute value of a Fourier transform, and sometimes power spectral density. If I understand co... |
I' trying to implement a QPSK modulation/demodulation.
At one point I have to decimate my signal by 4 for an easier implementation. I've read everywhere that the best way to do it is to use a CIC filter followed by a decimator. So I've read some more and I decided to use the following:
CIC Filter Length: 2
CIC Filter ... |
I have a problem with SIFT that I do not understand. Lowe [1] proposed in his work the s=3 levels of scale are enough for one octave. Afterwards, he mentioned that you need to compute s+3 levels.
Why there are 3 and not 2 additional levels required. I understand that you require one additional level above and one addit... |
I'm gonna implement multiple frequency estimation by summing harmonics amplitude!
I've read Anssi Klapuri paper but i can't understand him.
first of all he said spectral whitening i did it by i don't know whether it's true! after that i have to implement this formula:
$$s(\tau)=\sum_{m=0}^Mg(\tau,m)max_{}|Y(k)|$$
i ca... |
I want to estimate the direction of arrival of sound (angle in a 2d plane) using a microphone array. I'm hoping to follow a time-delay based method using a 4 mic array. The method requires me to find the time delay of the signal upon arriving at the different microphones. For example, in the 4 mic array, I'm required t... |
Suppose you have a transmission line carrying a digital signal and the line is picking up random noise such that half the bits in the original signal are randomly flipped before they reach the receiver. What techniques are available to recover such a corrupted signal?
|
for the (7,4) Hamming code, I know how to decode a codeword using the syndrome decoding method, by just using the 3 parity bits, and it is correctable if there is just 1 error.
However, for the (8,4) extended Hamming code, I know how to decode the codewords correctly when there is no error or 1 error respectively. Howe... |
The following is from Lowe 2004 paper ( http://www.cs.ubc.ca/~lowe/papers/ijcv04.pdf ).
One obvious approach would be to sample the local image intensities around the keypoint at the appropriate scale, and to match these using a normalized correlation measure.
However, simple correlation of image patches is highly sens... |
I'm trying to create two tones at different frequencies. So I have one tone at 15000 Hz and one at 15400 Hz using Audacity. The problem i'm running into is there is a third tone created at a much lower frequency I can tell exists from both my ears and a spectrogram.
How can I get rid of the lower tone? Where does it co... |
There is a Dirac pulse train following the scheme of the Shah function (or $\delta$-cumb function) with its Fourier series of the form:
$$\varsigma(t,T)=\sum_{n=-\infty}^{\infty}\delta (t-nT)=\frac{1}{T}\sum_{n=-\infty}^{\infty}\exp\left(\frac{i 2\pi n t}{T}\right)$$
here $n\in \Bbb Z$; $t$ time and $T(\in \Bbb N)$ the... |
If I have a sound recording with a sinusodial frequency with a constant amplitude and I do an FFT on the time domain of this recording to get the frequency back:
If I were to ignore the imaginary part and just watched the amplitude (real part) would there be anything different about it? Would it also be constant?
I'm t... |
In Harris corner detection, as I see, the goal is to find out those points $(x,y)$ which makes $S(x,y)$ a large value for any direction of shifting, $$ S(x,y) = [\Delta x , \Delta y]M\left[ \begin{array}{c}
\Delta x \\
\Delta y \\
\end{array} \right]$$, while $$M = \sum_{(x,y)}\left[ \begin{array}{cc}
I_x(x,y)^2,& I_x(... |
I begin to study how codec works, and I found a "summary-diagram" for DCT-codec (DCT stands for Discrete Cosine Transform). On this diagram, there are of course two steps: the encoding step and the decoding one. I try to make a reproduction of this diagram herebelow:
ENCODING STEP Image (8*8 blocks) -->| FDCT |-->| Qua... |
I have a set of 3D data points, indicated by the blue color in the picture below.
I then project them onto the x-y plane, i.e. setting z values of all the points to 0, shown by the yellow color below.
Then, I perform PCA on the 2D data points (the yellow ones).
I end up with the 1st Principal Component being the green ... |
I have a set of songs for which I extracted the STFT (Short-Time Fourier Transform) and used the magnitude spectrum $|S|$ to calculate the mel spectrogram by using a mel filterbank matrix $M$, so $X=\log(M\times |S|)$. I want to know is there any method to reverse this process, i.e. convert from the mel spectrogram bac... |
I am looking for a way to completely describe which kind of digital filters I used to process my data, although it seems only few publications in general report all the details.
I think I should describe at least
Which type of filter was applied (low-pass, high-pass, etc).
Cutoff frequencies
IIR / FIR
Phase response? ... |
For a current project I need to implement an algorithm that needs the autocorrelation sequence of the channel, as part of a key step.
We're measuring the frequency utilisation in our local area - simply be scanning the spectrum (from 440 MHz to 780MHz) with an SDR and collecting the power at each frequency. The goal o... |
I am new to signal processing and im trying my best to figure out how to build a high pass filter then later on implement it. (in c#)
Edit: I rewrote the question with math notation,
if someting is still wrong i will try to correct it. It is my first time to write a question in math notation.
This is to learn and for m... |
I've tried googling and wikipedia-ing it, but I haven't gotten any answers beyond 'it's because the frequency of the input signal is sitting between two bins'.
I understand that this is the reason, but what I can't understand is why the leakage seems to extend to several adjacent bins rather than only one adjacent bin.... |
I have seen this be mentioned a couple of times in some books I read, so I want to make sure. Is the complex envelope simply the summation of the real and quadrature components of a signal, whereby the absolute value is the (real) envelope? I have read this wiki page but I am not sure I completely understand. Is the co... |
I am running Morlet continuous wavelet transform. I have got wscalogram of signal and now I want to plot freq-magnitude like the following picture., but I don't know how to do it:
I've used scal2freq MATLAB function to convert scales to pseudo frequencies. Also I have some frequencies in my signal that have a large d... |
I'm trying to write a perona malik filter in HLSL
texture2D Input0;
sampler2D Input0Sampler = sampler_state
{
Texture = <Input0>;
MinFilter = Point;
MagFilter = Point;
MipFilter = Point;
AddressU = Clamp;
AddressV = Clamp;
};
struct VertexShaderInput
{
float4 Position : POSITION0;
float... |
I want to simulate a direct sequence spread spectrum (DSSS) system and the receiver works with matched filter. I want the received power to be different for each user, in other words, SINR shouldn't be 0. Is there any idea how to do that in matlab?
|
I'm currently implementing a voice recognition algorithm using FFT and now some questions came up to me:
Spectral Leakage: I know what it is, why it appears and how to solve it using a Windowing Function, but is there another work around for this issue?
Phase: I know what it is, but where can I use it and how?
Getting... |
In general, correlation-based image matching can be referred to as
$$c(I_1,I_2) = \sum_{x \in patch} f(I_1(x), I_2(x))$$
, I do think normalized cross-correlation like
$$ncc(I_1, I_2) = \sum_{x \in patch}\frac{(I_1(x) - \mu_1)(I_2(x) - \mu_2)}{\delta_1\delta_2}$$.
is a good indicator to show if 2 patches match or not.... |
How do I calculate the Spectral Entropy of a signal in MATLAB ? I know the basic steps but it would be nice if someone can help,
Calculate the power spectrum of the signal using FFT command in MATLAB.
Calculate the Power Spectral Density using the power spectrum or using any other technique.
Normalize the Power Spectr... |
As a follow up to this question -
Is there a way that I can calculate the amount of spectral leakage in a given bin, i.e., given an input amplitude, what percentage of the amplitude is present in the adjacent bins?
Or given an input frequency and the frequency range of each bin, can I calculate the amplitude present ... |
I'm working on Cognitive Radio in TV Band Spectrum. I need to sense the presence of signal in a particular spectrum. I have to sample the incoming signal (say 1000 samples) and I have to find the auto correlation strength for a smoothing factor L(means my sample will be 0 to L-1 samples delayed). I have assumed a smoo... |
Is there a simple or potentially intuitive explanation for, with the DFT, vector multiplication in one domain being equivalent to circular convolution of the transforms of the vectors in the other domain?
Since a DFT is just multiplication by a (special) square matrix, what about this matrix and matrix multiply allows ... |
I am working on a project that employs a linear array sensor that provides data from the same object at two different energies. Collected in time, I end up with two images (16-bit sensor values, MxM image), call one HIGH the other LOW. My engineering background is Material Science and metallurgy, so I am coming up to... |
I read the following on Wikipedia:
Power spectral density:
The above definition of energy spectral density is most suitable for
transients, i.e., pulse-like signals, for which the Fourier transforms
of the signals exist. For continued signals that describe, for example, stationary physical processes, it makes more... |
I have two images – mannequin with and without garment.
Please refer sample images below. Ignore the jewels, footwear on the mannequin, imagine the second mannequin has only dress.
I want to extract only the garment from the two images for further processing.
The complexity is that there is slight displacement in the... |
I am calculating spectrogram of a audio file of 36 second using the following code snippet:
window = np.hamming(window_width)
length = signal.size
count = 0
for i in range(0, length-window_width, window_overlap):
cur_frame = signal[i:i+window_width]
window_frame = cur_frame*window
spec = sp.fft(window_frame... |
I got curious based on this question here, but basically, is there ever a real-life signal that exists where its Fourier transform does not exist? If a signal is not finite energy, then its Fourier Transform does not exist, so what might be an example, (if any), of such a signal in real-life?
|
I started learning audio dsp and the book I am working through is loaded with formulas and most of the time expects the reader to know what the relation is between these functions and why they are being used in the first place.
I'd reading a section on spectral shape, which includes sub sections on rolloff, flux, centr... |
I need for an algorithm which do steps, displayed on image below.
Are solutions for doing this exist? (Preferably on C# or JavaScript).
|
I designed a 2nd type Chebyshev bandpass filter with passband between 1 and 6 Hz and 30 dB attenuation in the stopband. When I looked at its Bode plot in Mathematica, I noticed "stability margins" (black lines) on the plot. I'm not familiar with this concept.
Does the stability margin have any impact on the stability o... |
hmm any one can help please? I have a signal that contains some modes in it. I've run a CWT transform but I haven't got my desired results. so I implement a test signal that contains freqs [0.1,0.3,0.6] Hz to see whats the problem with my codes. but the result was accurate. once I change the freqs to [0.1,0.4,0.6] or [... |
My data is sampled at $f_s$, and I'm interested in analyzing certain frequencies $0<f_1<\ldots<f_N<\frac{f_s}{4}$. I then take $T$ samples of data, $\{x_1,\ldots\,x_T\}$ where $T\gg \frac{1}{f_s}$, FFT it after padding to the next power of 2 after $T$ and then pick the FFT bins closest to my $f_i$ of interest to procee... |
How can I compare the way that word is pronounced with a sample? For example, most of dictionaries have sample word pronunciation recorded. The goal is to provide feedback to the user so that he or she can improve pronunciation.
I wonder if there are API available for such task or existing programs that are able to do ... |
I'm trying to do an FFT on live audio to see its spectrum.
So I have a sampling rate of 44100 Hz and from this take out 1024 bins on my FFT
So to test it I play a continuous tone at 15000 Hz and another one at 16000 Hz and look for it on my spectrum. I try to use higher ones to cut out noise from around. I have made th... |
Please excuse me for asking such a basic question. I was having a look at how AM radio works. So there is a carrier frequency and a higher frequency inside that that carries the data.
Does this mean that there would be two frequencies, one high and one low?
What about for stuff like 3G/GSM when stuff is sent over EM wo... |
I require an image processor which compares an image with a set of images and finds the equivalent image out of them.
|
What is meant by "spectral whitening" in DSP?
What effect does spectral whitening have when used in image processing? (visually or otherwise...)
Where might spectral whitening be useful in audio processing or analysis? What would a spectrally whitened audio signal sound like?
|
I'm having some trouble understanding FFT plots and measures.
According to this, this will give me the magnitude plot of FFT, but I want the area under from 1 to 10 Hz for example.
Is this next formula I made right?
My doubt is, what's the relation between Hz and rad/s, f and w?
|
I'm looking for wavelets that are both:
causal (a wavelet coefficient $W(j,k)$, where $j$ is scale and $k$ is translation, does not use data from $t > k$ to be estimated).
complex (such as the Morlet wavelet, to analyze phase differences between two time-series).
Do any exist?
|
I am really sorry if it is wrong place to ask this question but i couldn't not find any stackexchange website appropriate.
i have some reflectance values of a material which are measured in 10.5 and 12.5 micrometers interval. This spectra is extracted from a spectral library. Then by using Kirchhoff's Radiation Law i c... |
Glottal Closure Instants (GCIs) are referred to the instances of significant excitation of the vocal tract.
I have seen in some papers that I can measure instant of glottal closure in a voiced segment directly from speech waveforms.
Can someone provide me information how detect GCIs ?
How Glottal Closure Instants can b... |
How is it possible to go from time domain amplitude values in floating point to frequencies?
I know the DFT is used, but what exactly is happening for it to be able to extract frequencies from amplitude values?
Is amplitude between -1 and 1 mapped from pressure levels? How are different frequencies detected in a block ... |
I am using Cmor-Fb-FC wavelet transform in matlab environment. Fb is bandwidth and Fc is center frequency parameters. with trail and error procedure I select Fb-Fc as 5-1, and I've got rational output. But I want to know whats the rule of selecting proper value for Fb-Fc parameters? Imagine I am using 300 samples over ... |
With Python/Scipy, if I have a simply BPSK signal sequence [1, -1, -1, 1, ...], how can I generate a real-valued baseband waveforms with oversampling rate m, and common pulse shapes such as root raised cosine, Nyquist, etc.?
In Matlab I found this fdesign.pulseshaping function, is there an equivalent function in SciPy?... |
I have a DS-CDMA system and the chip width is fixed but every user have a different spreading code length. I want to have a simulation of signal to interference noise ratio (SINR) VS. bit error rate (BER). If I assumed that SINR is given like -25:0 dB. How can I calculate noise power (it is thermal noise) and the inte... |
I read that an "improper system" "has more zeros than poles; it is not causal, cannot be implemented, has a strictly proper inverse and has infinite high-frequency gain."
Does causality fail due to instant signal change? I try to make up a recurrence, where $x_n$ depends on both $x_{n-1}$ as well as $x_{n+1}$ but they ... |
I have data from a LIDAR unit that I would like to get the spectral density of. Unfortunately, the only thing I remember from my Fourier analysis class are the methods that I know will not work.
The data comes from a 1D LIDAR scan of a (mostly flat) surface, which returns radial distance at evenly spaced $d\theta$'s. I... |
I know that to downsample by a factor of 2.5x one can upsample a signal by a factor of 2 and downsample by a factor of 5. I am wondering what is the best and more efficient way of downsampling by a factor of 2.5x?
|
I have a few questions regarding the implementation of Bark scale filter banks for the calculation of bark frequency cepstral coefficients.
1) Which filter shape is most commonly used and why?
Triangular band pass similar to the mfcc's as seen here:- A Comparative Study of Filter Bank Spacing for
Speech Recognition
Tr... |
I know that the Complementary Filter has the functions of both LPF and HPF. But I think my understanding on the principal behind it is still unclear.
I am quite new on digital signal processing, and maybe some very fundamental explanations will help a lot.
Say I have a Complementary Filter as follows:
$$y =a\times y+(1... |
This is my first question at this site, please excuse me if I'm not asking the question properly.
I have an acoustic signal of a test and I want to remove the "thin" peaks, because they don't really affect the structure that I'm studying. For that I've thought of a Low pass filter in order to retain only frequencies b... |
I'm trying to decode a Hamming Block Code transmitted using a QPSK modulation.
For the moment I can sucessfully decode it using hard decision but in order to improve performance I'd like to use soft decision. I've read some online courses about the Viterbi decoder and I think I understand how it works.
The thing is tha... |
From a book, I learned that image interpolation (or upsampling) can be written as a convolution like this:
$$g(i,j) = \sum_{(x,y)}f(x,y)h(i-rx,j-ry)$$
while $r$ is the upsampling rate.
But I have a time understanding this formula, since AFAIK, the basic idea of image interpolation is to bring near-by pixels into consid... |
I am attempting a project and I have been given bat calls (in .wav format) which are not ultra-sound navigation calls. I'm looking to isolate the different species of bats and monitor their activity.
The problem I am having is that I do not have a prior training set to be able to feature matching on the samples to try ... |
I read several papers which proposed a method to identify modal parameters. such as natural frequency and damping ratio.I've tried to implement those methods by Matlab.but I couldn't get the result.It seems I missed something.anyway it must be some problem with my codes.Please check it and see what's the problem. here ... |
Remember that Christopher Walken skit on Saturday Night live where he told the band “it needs more cowbell” https://en.wikipedia.org/wiki/More_cowbell ? This site automated it http://www.morecowbell.dj/ using echonest http://developer.echonest.com/ . That’s all fine. Question is: “What is the actual algorithm behind... |
I have two electric signals from different sources and I think that are similar.
I have the FFT of the signals and I have their spectrums of frequency in separate arrays.
How should I proceed to find the percentual of similarity the two signals?
|
I'm having some problems understanding the FFT. Is the frequency resolution in the spectrum calculated as
$\frac{\textrm{sampling rate}}{\textrm{number of FFT points}}$ or $\frac{\textrm{sampling rate}}{\textrm{0.5 * number of FFT points}}$?
Asking this because the spectrum is symmetric for real-valued inputs. So, say... |
I have some biomedical signals. If I calculate their magnitude spectrums, I see power-line interference at 50 Hz. I was excepting a harmonic at 100 Hz, but it turns out there is none. However, there is a harmonic at 150 Hz. Is this common or should I worry that I have done something wrong?
|
As the title suggests , I want to know how noise cancellation is achieved by adding multiple images together . I know the theory behind it , but simple adding the pixel values of 100 noisy images of the same sample would simply produce a white image . Can anybody elaborate , how it is normally done.
|
What exactly is one looking for in audio data to find different instruments or energy sources?
So the FFT can extract frequencies, but how can e.g. percussion be detected alongside e.g. a bass line?
Would the frequency bins be checked into a frequency mapping of instruments? This would lead to collisions in possible in... |
As a beginner in signal processing, i'll try to explain my problem most thoroughly.
I'll firstly explain the idea of the transformation the real valued data has undergone.
This includes the ideas and reasons why it does work and the way to revert the procedure. Then i'll explain my difficulties in reverting it.
First o... |
Is there any approximate relation in FFT coefficients?
For example, consider time domain signal $x_n$. Its $N$ point (assume $N$ to be even) DFT is given as $X_0,X_1,...,X_{N-1}$
Can I say something about the nature of $abs(X_1)/abs(X_0)$? I am trying to see the variation in DFT coeffcients and for that I thught one ca... |
The shift theorem says:
Multiplying $x_n$ by a linear phase $e^{\frac{2\pi i}{N}n m}$ for some integer m corresponds to a circular shift of the output $X_k$: $X_k$ is replaced by $X_{k-m}$, where the subscript is interpreted modulo N (i.e., periodically).
Ok, that works fine:
plot a
N = 9
k = [0, 1, 2, 3, 4, 5, 6, ... |
Why exactly is X(0) the DC component of a signal?
How is it equal to N times x(n)'s average value and why it is at X(0)?
|
I'm fairly new to digital signal processing. I've been trying with limited success to apply a time-varying bandpass filter to a signal (question at stackoverflow). Instead I thought I'd try a different approach. Say I have a function which approximates the data I'm trying to filter from my signal. Is there a technique ... |
I have a sinusoidal signal embedded in noise, and I would like to estimate it's amplitude and frequency, so I can subtract it out.
I realize that an FFT can do the job for me, and that's what I've been doing - I took an FFT of the input signal, and looked at the frequency bin with the highest amplitude, used that as an... |
I'm new to image processing, and I'm trying to get my feet wet. I have taken a picture of some jigsaw puzzle pieces and I want to isolate the pieces.
I am using the Python SimpleCV library to do this, and so far I've managed to get pretty decent results using findBlobs(), hueDistance(), and drawMinRect(). Here's what ... |
I am reading a book on filter design and the author mentions to evaluate a transfer function, let 2 * PI * f (w) vary from 0 to PI to get the first half of the response.
How exactly is this done in code and what is meant by vary in terms of actual values?
Should f not change as well to get the response of different fr... |
what would be the most efficient ("cheap" in terms of system resources etc.) way to compare 2 sound files?
Here is the scenario. Sound A comes as an input. There is sound B stored in memory. We need to see if sound A is identical to sound B. We know that both sounds can be copies of the same sound file, but there is a... |
I am new to the topic of compressed sensing. I read a few papers about it by R.Baranuik, Y.Eldar, Terence Tao etc. All these papers basically provide the mathematical details behind it, i.e., Sparsity, RIP, L1 norm minimisation etc. However, can anyone provide the MATLAB codes that achieve compressive sensing?
Thanks i... |
I am in need of an open source library for computing Fast wavelet transforms (FWT) and Inverse fast wavelet transforms (IFWT) - this is to be part of a bigger code I am currently writing.
The things I am looking for in the library:
1) Contains a good variety of wavelet families (Daub,Haar, Coif etc.)
2) Ability to run... |
I have a signal which consists of an onset and a release period.
The onset, sounding like a thud, excites frequencies across the entire frequency range (0-22 kHz). It lasts for about 0.1 s.
The release, sounding like a ring, excites 2-5 specific narrow frequency bands. Their amplitudes decay exponentially, albeit at s... |
Wireless networks operate on a high frequency, say some several gigahertz. Are the signals really sampled at that high frequencies? If I got it correctly there's some modulating/demodulating in signal transmit, does that effect the situation somehow?
|
I'm trying to recreate a gassuain pyramid using the following scales:
There seems to be two concepts used here:
1) When an image is halved, applying a gaussian kernel of σ will apply as 2σ.
2) When an image has a scale of σ, and a gaussian kernel of σ is applied, then the resulting image will have a scale of sqrt(2)*σ... |
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