0
votes
0answers
7 views

Extreme audio stretching

This tool (Paul's Extreme Sound Stretch) is able to produce extreme timestrech (50x, or even 100000x). Any song can become an interesting sound texture or ambient music (listen to this example). The ...
0
votes
1answer
7 views

Is the system $L\{f[m,n]\}= c[m,n] f[m,n]$ shift invariant?

$c[m,n]$ is the spatially varying gain. My prof says that its not shift invariant. However if we put $m=m-k$ and $n=n-l$ we get $c[m-k,n-l] f[m-k,n-l]$ which is how a shift invariant system should ...
0
votes
1answer
10 views

Bilateral z-tranform of exponential

We all know that $a^nu(n)$ has unilateral $Z$-transform. But what is the $Z$-transform of $a^n$? (bilateral) When i tried to solve, i got answer as 'zero'. But bilateral Laplace transform of $e^t$ ...
0
votes
0answers
3 views

How to find the security of an encryption technique?

Is there any equation to show that a new encryption is more secure. Since it is required for theoretically showing the result. The encryption is implemented using matlab. Plz help me to find the ...
0
votes
2answers
18 views

Creating a flat spectrum filterbank

I'm trying to create a filterbank whose frequency response is generally flat when summed in parallel. Are there any tips to choosing center frequencies and bandwidths for a filterbank of overlapping ...
0
votes
1answer
26 views

Frequency Spectrum with c++

I have written a script to plot the frequency spectrum of a sinusoidal signal with c++. Here are the steps 1-Applying Hanning window 2-Apply FFT using fftw3 library I have three graphs: Signal, Signal ...
1
vote
1answer
13 views

Extracting direction of dominant sinusoids from an image in terms of angles

Here is a sample image. What I am looking to do is compute the dominant "wrinkle" directions. The dominant wrinkle directions can be seen in the following FFT, roughly, by drawing a line through ...
1
vote
2answers
13 views

2D Haar Transform Computational Complexity

I want to learn the computational complexity of the 2D Discrete Haar (Wavelet) Transform (DHWT). The number of operations (divisions, summations etc.) is the main focus. I think there are many ...
0
votes
1answer
36 views

FIR filter design for response inside unit circle

I would like to design an FIR filter such that its Z-transform has a certain profile in certain regions. For example, if I'd like to have an FIR filter that nulls the decaying exponential ...
0
votes
0answers
8 views

Role of HMM in speech recognition [duplicate]

What exactly hidden markov model does in speech recognition process? I read it is the representation of phonemes as states? What exactly is a state? Any detail article on HMM role in speech ...
1
vote
3answers
43 views

Apply the Hamming window to a sinusoidal signal

I am a novice in signal processing. I am writing a code to apply the hamming window to a sinusoidal signal. So first I have digitized my sinusoidal signal by choosing a sampling rate more than twice ...
3
votes
1answer
30 views

Proof from wave equation of upper limit of active noise cancellation

Anybody know of a proof of the hard upper frequency limit of active noise cancellation using the ear canal volume as a boundary condition to solve for the upper frequency limit? I keep on encountering ...
0
votes
1answer
55 views

What is the name of the following 1st order high-pass IIR filter?

What is the name/family behind the following high-pass IIR filter: $ T = 1/f_s \\ f_c = 5 \\ c_1 = \displaystyle \frac{1}{1 + \tan(\pi f_cT)}\\ c_2 = \displaystyle \frac{1 - \tan(\pi f_cT)}{1 + ...
1
vote
1answer
46 views

Conversion of FFT to PSD

I would like to convert FFT data which is set of 396 values for 396 frequencies (from 4Hz to 399Hz by 1Hz) in unit of g's (gravitational akcceleration) to PSD in unit of (g^2)/Hz, is it possible? ...
0
votes
0answers
21 views

DFT calculation for different sampling Frequency

while representing a sinusoidal signal in DFT, we will be knowing the Sampling frequency. for example let input signal frequency is 50Hz, and sampling rate is 16, then sampling freq is 800 suppose ...
1
vote
1answer
35 views

Power Spectrum Analysis

In order to find a peak or max response in the fourier domain as in the spatial domain, I have been studying bartlett's method, welch's method, and the blackman-tukey method for more accurate power ...
0
votes
0answers
7 views

Common spatial patterns explanation

Can anyone provide a lay explanation of what common spatial patterns are designed to do in EEG/BCI work? From what I understand, it is similar to PCA in that given 2 classes, it attempts to find a ...
1
vote
3answers
52 views

Algorithm for detecting the time where the signal is above a threshold

I need to detect the time window where a 1D-signal is above a certain threshold. If it dips below the threshold briefly I'd like to merge the two windows, if it dips below for a longer time, split ...
1
vote
2answers
63 views

Complex low pass filters

I am searching for documentation on the behaviour of complex low pass filters, and their application in telecommunications. Thank you
1
vote
1answer
24 views

Equalization knowing the Channel State Information

I am trying to simulate a simple communication system using channel estimation. I was able to estimate the channel response using the Least Squares channel estimator, and it is working properly ...
0
votes
2answers
30 views

How can JPEG 2000 be implemented using MATLAB? [on hold]

I am new to image processing and image compression. It would be great if someone could specify which functions would be useful for doing so.
0
votes
0answers
5 views

Internal constaint of essential matrix

I work on visual odometry program and I use EmguCV. I use calibrated camera to detect features from current frame with SURF, and match them with previous using Knn. Because I have calibrated camera I ...
1
vote
1answer
56 views

How to prove $\int_{\Omega} \sum_{i=1}^{N} f_i(x)dx$ is equivilant with $\sum_{i=1}^{N} \int_{\Omega} f_i(x)u_i(x)dx$

I have a 2D image defined on a region $\Omega$. Assume that the region can be separated into $N$ sub-regions $\Omega_i$ such that $$\forall i,j=1... N:\Omega_i \cap\Omega_j=\emptyset$$ and ...
0
votes
1answer
40 views

DFT for audio classification - signals of different lengths

If I have a set of signals each with $n$ points, I can take the DFT of each and then use the resulting frequency domain vectors as features for some classification algorithm. If the signals are ...
0
votes
0answers
10 views

To estimate the uncertainty of Slicing holes from an image?

I am thinking to estimate the uncertainty of holes photographed from the bottom and top side. The difference of the same hole photographed from two sides is distributed as Gaussian. The length of ...
-1
votes
1answer
22 views

Nyquist Rate Determination

If the Nyquist rate for xa (t) is Ωs, what is the Nyquist rate for xa(2t)? Will it be the same, increase 2 folds or decrease 2 folds?
4
votes
0answers
40 views

Kalman filter restricted by areal constraints

I'm developing a device for tracking pets in a room with several motion detectors. I use a Kalman filter to estimate the position, which is based on the active outputs of the motion detectors. If an ...
0
votes
0answers
11 views

Reconstruction from eigenfaces

Could somebody give me an example of a reconstruction of a face from eigenfaces? I understand most of the process, but I do not understand how the reconstruction works Thanks
0
votes
1answer
16 views

Understanding Eigenface Face Recognition Algorithm Notations

I have been reading the paper from Matthew A. Tusk and Alex Pentland https://www.cs.ucsb.edu/~mturk/Papers/mturk-CVPR91.pdf I got stuck in this part. I have a couple of questions. Assume my ...
0
votes
0answers
20 views

Complex Gaussian Channel + AWGN noise

If I define a channel to have complex Gaussian coefficients, do I still need to add noise to the signal passing through this channel using the command "awgn" or would that be redundant? Thank you. ...
0
votes
1answer
29 views

what is the differnence between 8x8 dct coefficients and 25 x 25 dct coefficients?

As I knkw the DCT is discrete cosine transform that mostly used in time domain analysis to frequency domain. Also 8x8 is used in nomaly in img processing. I don't know why that is defined by 8x8 ...
0
votes
0answers
14 views

How to calculate binocular overlap

I have two cameras of which I know focal length, principal point, rotation and position. The cameras are in an ideal parallel stereo system. I want to know with as few calculations as possible how ...
0
votes
0answers
17 views

what is magnitude responce at ω = π/2M for freqz function [duplicate]

what is magnitude responce at ω = π/2M.Code Given is ...
3
votes
0answers
16 views

Why wavelets based transmitter/receiver digital signal processing aren't common?

I have seen this thread: Difference between Fourier transform and Wavelets AFAIK there is no common usage of wavelets in the real-time DSP world (excluding image and video processing). I am curious ...
0
votes
4answers
51 views

Why is a wavelet transform implemented as a filter bank?

The mother wavelet function $\psi(t)$ must satisfy the following: $$\int\limits_{-\infty}^{+\infty} \frac{|\psi(\omega)|^2}{\omega} d \omega < +\infty,$$ $$\psi ( \omega ) \bigg|_{ \omega =0} ...
1
vote
0answers
11 views

How to reduce reconstruction noise from a filtered back-projection reconstruction of a circularly symmetric image?

I need to perform tomographic reconstruction of an axially symmetric object. Because of the axial symmetry only one projection of the object (one angle) was taken. I implemented the filtered ...
0
votes
1answer
29 views

Circular Convolution of h(n)*x(n)

So I understand how Convolution works but Circular convolution seems a bit messy to me, all the examples seems to have even series of number like h(n)={1,2,3,4} & x(n)={1,2,3,4} and they are all ...
-1
votes
0answers
30 views

Is this a DC offset problem or an aliasinge effect?

First of all, please be gentile it I have very little experience with signal processing. Any way, I am trying to decode a RF signal between two RF boards.... but the signal I am receiving is a little ...
1
vote
0answers
7 views

Probability of Detection and pulse-pulse decorrelation time

Not sure if this is the right forum, but thought I'd ask anyway: I'm trying to analyze the probability of detection ($P_d$) for a Swerling II target. I know that the Swerling II target assumes that ...
0
votes
0answers
23 views

Building a distributed low-pass filter with cutoff frequency of $1$hz but the highest frequency of $10^{6}$hz

How does one build a distributed low-pass filter with cutoff frequency of $1$hz and highest frequency of $10^{6}$hz (or arbitrarily high)? In case of lumped circuits, this is easy to do, but in case ...
1
vote
2answers
113 views

Is there a condition for bandpass sampling?

Consider a signal that has lowest frequency component $F_l$ and highest frequency component $F_h$. According to the theory of bandpass sampling, this signal can be sampled and succesfully recoverd if ...
1
vote
1answer
30 views

Difference b/w freqz and fft

Since both fft ,freqz are used for finding the frequency response of digital filters. the frequency response using freqz function is given below and frequency response using fft function is it ...
0
votes
0answers
46 views

how to correct minBLEP sawtooth oscillator DC bias

In my implementation of minBLEP, overlapping minBLEPs result in a DC bias as the frequency increases. This is because each minBLEP correction (i.e. the minBLEP minus the aliased step) has a DC bias. ...
0
votes
1answer
36 views
0
votes
0answers
16 views

Audio processing with transformation [on hold]

Can I use bilinear transformation on audio? What will be the output? Some co-efficient like fourier transformation?
0
votes
0answers
22 views

distributed low-pass filter frequency range

Suppose that signal's frequency ranges from 0 to some very high frequencies. One builds a low-pass filter which needs to be based on distributed element analysis because lumped-element analysis is ...
0
votes
1answer
19 views

If I build a low pass gaussian filter in the frequency domain should I also normalize it with the sum of the filter coefficients?

I saw two examples of applying a Gaussian low pass filter to a Matlab image: one- when the filter was built in the space domain and was normalized with the sum of the filter coefficients, and another- ...
-1
votes
0answers
13 views

I want know if the inverse Laplace transform is correct [on hold]

I want know if the inverse Laplace transform is correct $$ L^{-1}\left\{\frac{e^{- T_d s}} {s (1 + \tau s)}\right\} = \left(1 - e^{- \frac{t - T_d}{\tau}}\right) u(t - T_d) $$ where $ u(t) $ is ...
0
votes
0answers
33 views

Frequency Domain Equalization [Sources request]

When I read papers, I often see the term "Frequency Domain Equalizer". I do not understand what a "frequency domain equalizer" is. Do they mean equalizers like MMSE, LMMSE? Or is there an equalizer ...
0
votes
1answer
34 views

Can you explain about the following formulas? in Signals and System

In my textbook, any signals could be expressed like the following formula. $x(t)=\displaystyle\frac{a_0}{2}+\displaystyle\sum_{n=1}^{\infty}[a_n\cos(2{\pi}nft)+b_n\sin(2{\pi}nft)]$ I understand that ...

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