0
votes
0answers
8 views

Basic “filtering” in digital communications

I am completely stuck on solving some problems for my digital communications class. Junior level undergrad class, so fairly basic. I have been searching around all day for related articles etc but ...
0
votes
0answers
3 views

FFmpeg audio filter pipeline for speech enhancement

Using ffmpeg, I'm recording a talk, its audio with a semi-distant microphone. It makes sense to somewhat enhance the speech clarity, reduce background static and ...
-1
votes
0answers
11 views

Classification SVM

I have a problem with Support Vector Machine classification. I have two classes of children (boys and girls). I use a MFCC function for training (for each class I have 24 coefficients, number of ...
-4
votes
0answers
24 views

how to calculate noise power

I want to calculate the noise power after getting received N samples of noise, I should implement this in C++. Here is my code and I think that is not correct ...
0
votes
2answers
50 views

Transfer function block diagram

Can any one help with the $y[n]$ and $x[n]$ relationship in this block diagram, I just keep have a $t[n]$ in my answer that I can't get rid off. On my best try I got to $y[n] = ...
0
votes
0answers
24 views

Extract amplitudes

I have two mixed signals like $A_1f(t) + A_2g(t)$, where $f(t)$ and $g(t)$ are sinusoidal. I want to extract the amplitude infos. Directly I can not get the amplitudes (or I don't know how to). What I ...
0
votes
1answer
19 views

How to compare the qualities of two interpolation (image resizing) algorithms?

I am implementing image resizing algorithms (Bilinear, Bicubic, Lanczos and a few others). How do I quantitatively compare them? I am thinking of considering a large sample of images and running ...
0
votes
1answer
25 views

Matlab FIlter coefficients to CMSIS api

I am trying to implement iir Band Pass filter design in STM32F429i discovery kit. I konw that it needs coefficients to be generated from matlab and feed them into cmsis api to achivi filtered data. ...
-1
votes
0answers
3 views

mpeg-4 compression format to digital cinema format

how will we convert MP-4 video compression format to digital cinema or ultra high resolution format?
0
votes
0answers
15 views

Difference Between Least Square Error Recognition, Logistic Regression, and a Certain Nearest Neighbor Neural Network

Least Square Error Recognition from JavaOCR finds the least mean square error from a training image pixel by pixel. Logistic regression from this site, on the other hand, seeks to minimize the error ...
0
votes
0answers
19 views

How will sampling alias affect periodicity shown in samples of a continuous infinite-time signal?

Suppose there's a continuous infinitely-lasting signal $f(t): \mathbb{R} \to \mathbb{C}$. It is known that $f(t)$ only has non-zero signals at finite number of frequencies. It is also known that ...
1
vote
2answers
33 views

Periodicity of discrete time signal: $ x\left [ n \right ] = \cos (\frac{\pi n^{2}}{8}) $

I need to find the periodicity of the following signal: $$ x\left [ n \right ] = \cos (\frac{\pi n^{2}}{8}) $$ Now I understand that the basic procedure to determine the periodicity is to find a $ N $ ...
-1
votes
0answers
19 views

Find the essential bandwidth of rect function? i want the ans by using Energy spectral density and then essential bandwidth… [duplicate]

I am trying to find EBW of rect function but i am unable to solve the integral after finding the fourier transform and then apply parseval's theorem?
-1
votes
0answers
15 views

Linear combination that minimizes the variance of a matrix

Can you please tell me is there a linear combination that minimizes the variance of a matrix. I have tried to use PCA with eigenvectors corresponding to the smallest eigenvalues but results remain ...
0
votes
0answers
36 views

Recognize musical instrument timbre

I have an audio recording and I need to understand what muscial instrument belongs. I read somewhere that a timbre depends on harmonic ratio, but how I analyze this ratio? With FFT? Any advice is ...
0
votes
0answers
27 views

how to plot the following figure in matlab [on hold]

can you please tell me how to plot the following figure in matlab,is there any inbuilt command or we have a logic .please help.
1
vote
0answers
13 views

Reference Request : How to compute CRLB to show the estimator is minimum variance

In system identification or parameter estimation, various input signals are used for exciting the process models. I am interested in parameter estimation of time series model using pseudo random ...
0
votes
0answers
30 views

What is the advantage of weighted median filter over median filter?

I could not find any proof or comparison of weighted median and median filters.Yes the more occuring pixel contributes much but what should be the criteria of choosing weight function.And any ...
0
votes
1answer
18 views

How to design a delay and sum beam former with fractional delay less than one sample?

I am supposed to design a delay and sum beam former for a short audio. But the sampling frequency is only 8kHz and after times the delay, the fractional delay is less then one sample, and after the ...
0
votes
2answers
33 views

Fourier Synthesis With Varying Frequencies Over Time

I'm doing some fourier synthesis by making bins of complex numbers, filling them out with the amplitude and phase information and using IFFT to turn that into time domain samples. I'm able to make ...
-3
votes
0answers
11 views

Frequency function $Y(\omega)$ and Spectrum $\Phi_{y}(\omega)$ difference

What is the difference between a frequency function of a signal $Y(\omega)$ and the spectrum of a signal $\Phi_{y}(\omega)$ ?
0
votes
1answer
28 views

2 points and instantaneous phase sufficient to estimate amplitude and frequency of sinusoid?

If you have 2 points (x1y1,x2y2) in a Cartesian grid, there are an infinite amount of sinusoids that pass through them. But if you are also given the instantaneous phase (Th0) in radians or degrees at ...
-2
votes
0answers
8 views

Wavelet transform on vibrations

I am working on wavelet transformation on vibration signals. I have data with displacement values, I had performed 'wavedec' function on my signal. I obtained the corresponding aprox. coefs and det. ...
0
votes
0answers
23 views

Sparse Signal Dense Noise

If I have a sparse signal contaminated with dense noise, and if I don't have a reference signal to help me, what techniques are suitable to recover the signal? I don't know what the original signal ...
0
votes
1answer
29 views

How to prove: high-slope/more change is high freq part of signal

Generally, everyone knows that "the part of signal with high-slope is the high frequency part." What is the definition or theory behind it? How to prove this well-known thing? perhaps, I miss ...
0
votes
0answers
12 views

sampling frequency of a bandpass modulated signal

If the input signal is 3khz and the carrier signal is 10khz what will be sampling frequency of the modulated signal if the modulation is bandpass modulation?
0
votes
0answers
15 views

Sinogram Fourier Analysis Doesn't Show Clear Bow Tie Shape

I'm working on finding the center of rotation of a set of test tomographic projections in order to perform 2D reconstruction. I'm trying to implement the algorithm to find center of rotation as ...
0
votes
1answer
26 views

Is there a closed form expression for noise other than white noise?

For white noise, where the PSD is constant, we can model that as a simple Gaussian. Is there any way to model the probability density function of other types of noise (pink noise, red noise, blue ...
2
votes
0answers
21 views

The channel capacity with additive Gaussian noise with changing variance?

As we all know the capacity for a AWGN channel with constant noise variance is just given by $\frac{1}{2}\log(1+SNR)$. What if the variance of the noise changes with the type (assuming the variance ...
0
votes
1answer
24 views

Deriving Time-Series Data from PSD when the Inverse Fourier Transform doesn't converge

So I'm trying to get some sample time-series data from pink noise (PSD: $S(f) = 1/f$). However, when I try to evaluate the Inverse Fourier Transform integral $\int \frac{1}{\omega} e^{j \omega t} dt$ ...
0
votes
0answers
11 views

regionprops vs. findContours doesn't find the same contours

Is there a way to get the same results for cDist=regionprops(bwImg, 'Area'); and openCV's findContours? Here is what I have tried so far: ...
0
votes
1answer
17 views

What is spatial correlation?

What does the spatial correlation of a signal say about it?How is it different from autocorrelation? `
0
votes
1answer
43 views

Calculating FIR filter coefficients with the windowing method and Convolution algorithm

Please advice how to calculate FIR filter coefficients with the windowing method using the Rectangular Window function and convolution method? What utility or FIR design application can perform this ...
0
votes
0answers
24 views

Calculating SNR for ECG signals

I'm reading through the literature for finding the best way to calculate SNR for a ECG signal. While there are many algorithms for improving SNR, I couldn't find any that details any standard ...
0
votes
0answers
5 views

Extracting coeff_token from h264

I'm trying to parse an h264 stream and I've run into trouble trying to figure out how to extract coeff_token from the stream. The spec doesn't seem to say how you are supposed to know how many bits to ...
2
votes
0answers
25 views

How to subsample shift with sinc interpolation?

Does anybody know of a way to shift data by a fraction of a sample by using sinc interpolation? For example, shift an image to the right by 0.1 pixels. I'm struggling to find a formula or reference ...
0
votes
0answers
10 views

What is the best way to detect audio drops (audio level drops irregularly) in a video?

While recording a video, due to some problem in microphone (like low battery ) audio level go down inconsistently (voice____Voice__), I am trying to figure out an solution for this, is there any way ...
0
votes
1answer
37 views

Sharpen defocused image

Using OCR, I want to extract text from product packages using Google Glass. However, because of the fixed focus of the camera the package pictures are blurred. Is there a way to sharpen the image? ...
0
votes
1answer
26 views

Determining Power Spectral Density from Autocorrelation Function and Time-Series Data

So I think I've confused myself a bit here. I know that taking the FFT of time-series data (wind velocities, for example) yields a power spectral density. However, I just read that taking the Fourier ...
0
votes
1answer
18 views

Diagonal vs non diagonal processing for audio denoising

I am going through a technique for audio denoising by block thresholding. Here is the paper: http://www.di.ens.fr/~mallat/papiers/AudioBlock.pdf According to the definition in the paper for ...
0
votes
1answer
31 views

What is the Sound of a Solution to the Wave Equation?

What is the sound of a solution $y(x,t)$ to the Wave Equation $\frac{\partial^2y}{\partial t^2}=c^2\,\frac{\partial^2y}{\partial x^2}\enspace$? To be clear, I don't look for a solution of the Wave ...
0
votes
2answers
19 views

Finding amplitudes from FFT data of a 2D image

I'm working on experiments with 2D - wrinkled surfaces. Basically I am getting a bunch of images like this. This example is hand-made. Is there a method to find the amplitudes of the first few ...
1
vote
2answers
54 views

Distorted output of delay VST effect in C

I'm getting some odd results with some code I'm working on. Help me with the implementation of this delay effect? The code takes an input, adds delayed input to it and then passes it to the output ...
0
votes
0answers
27 views

How to define cyclic frequency for cyclostationary signal in terms of signal parametrs?

I am trying to detect cyclostationary signal. For that it is required to know its cyclic frequency. But I am unable to figure out how it can be related to signal parameter. Is it possible to define ...
1
vote
1answer
39 views

Isolate the non blurred part of foucsed image

I have an image taken by a mobile phone camera with focus on a part of it let say a face or whatever. I want to know -approximately- where is the focused area. For example, a bounding box around the ...
-4
votes
1answer
27 views

What programming language is going to use MATLAB programming? [on hold]

Is this possible to work with PYTHON or C in MATLAB.
1
vote
1answer
47 views

Cross correlation with short signals?

I am a total newbe to signal processing and i have a problem which may be quite trivial to most of you guys. I want to align two short sensor signals (speaking of max. 1000 samples recorded with ...
0
votes
1answer
34 views

Understanding my Butterworth filter

My input is x and my filtered output is y. The sampling rate of x is ...
0
votes
3answers
31 views

What's the sampling frequency when synthetically generating data?

Say I am using matlab's random number generator to get an array of random numbers, which I will then, for testing purposes, find the spectral density etc. For that purpose I need to know the sampling ...
0
votes
0answers
5 views

History of emotion (or affect/prosody) recognition (or detection/analysis)?

I want to know how and why emotion recognition started. What I've come up with so far is an article from 1995: McGilloway, S., Cowie, R., & Douglas-Cowie, E. (1995). Prosodic signs of emotion in ...

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