MATLAB (MATrix LABoratory) is a numerical computing environment and a fourth-generation programming language. Use this tag with care.. see excerpt.

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how to overlapp and add the frames after applying some modification in time domain

I am trying to apply Dynamic range compression (DRC) in time domain in matlab. But I am having problem in overlapping and adding the frames. Somebody please help. Here is my work- ...
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1answer
48 views

Obtaining the FFT of a data set collected through an accelerometer

I'm using MATLAB to analyse a very large sample of acceleration data collected using the MPU9150 IC. My aim is to plot the FFT for this large sample of data. The daya is of three axes; $x,y,z$ and I ...
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16 views

adjust contrast of an image to negative percentages in matlab [on hold]

I need to change contrast of an image to negative percentage. I use imcontrast(), but when I set negative percentage it raises the below error: ...
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0answers
16 views

matlab error “The 'Gamma' property must be greater than or equal to 1”? [on hold]

I need to change gamma of a picture and reduce it to 0.6. but when I run below line of code in matlab: ...
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1answer
33 views

Difference between fft(signal, nfft) and fft(signal)

I want to know the difference between these following commands (matlab) and why I get two different outputs? fft(signal); fft(signal, nfft); I found that ...
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1answer
38 views

What could be causing these humps every 10 Hz on my PSD estimate data?

I am working with EEG recordings about 1,000,000 data pts long, recorded at 4,000 Hz. I'm generating PSD estimates for these recordings using the matlab "periodogram" function like so: ...
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1answer
20 views

Problem with Generalized Cross Correlation (PHAT filter)

I have to calculate time delay between two signals.I am using the GCC-PHAT method. First, I cut the signals into smaller parts (~0.5s) and then try to calculate the delay. When I display those two ...
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2answers
31 views

Bandpass Filter Order vs Sample Numbers of Noisy Signal

I'm working on signal filtering in MATLAB. i wrote sample code that generate 50 Hz signal with some noisy frequency and use Kaiser bandpass filter to get only 50Hz frequency. this code work great! but ...
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1answer
34 views

Noisy signal filtering matlab

I'm currently working on rectifying a respiratory noisy signal shown below: I've already tried to filter the noise as you can see in the image below (full image): The red one is the noisy signal ...
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16 views

Plotting band-pass filtered signal of an audio in MATLAB [closed]

I am new in MATLAB and try to plot some form of an audio file and I have managed to open and plot in time domain and FFT using the following code: Step I: Opening the Wave File ...
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1answer
56 views

Plotting Power Spectrum (Matlab)

I want to make a plot of the power spectrum for a .wav sound file, over the frequency range from -2000 to 2000 Hz. Attempt: I used the following code, but the resulting plot is one sided. It doesn't ...
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20 views

Problem with stft using matlab / python [closed]

I am trying to translate the code from Python to Matlab. The original code is written by Assoc. Prof. Xavier Serra from UPF and is a part of the Sound analysis/synthesis tools for music applications: ...
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1answer
20 views

Designing a root-locus compensator to attain design requirements

I am working with Matlab to design a compensator capable to make a system attain the design requirements ($\omega_n\geq 0.3$ rad/s & $\xi\geq 0.5$). In order to do so I have a discrete-time ...
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2answers
59 views

Filter Design in Matlab

I want to design a filter to remove all frequency components from a .wav file except those within $\pm 25\,\text{Hz}$ of $523\,\text{Hz}$ as well as its harmonics (up to the Nyquist frequency). ...
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18 views

Plotting Filter Transfer Function (Matlab) [closed]

I want to plot the absolute value and the argument for the following transfer function around $\nu = 400 \ Hz$. The filter has impulse response: $ h(t)=50 u(t) \exp(-10t) \sin(2 \pi 440t).$ (The ...
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38 views

Does the code length depend on Shannon's Source Entropy?

I am trying to calculate the number of bits required to encode a message. FOr that, I am applying Shannon's entropy. What is the minimal length? For a source message, $M$ of length ...
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0answers
46 views

How to shift a signal to the center of the frequency domain?

Let's assume I have a 1024 x 1024 matrix that represents the spatial domain. After I perform a FFT and center the frequencies, I get the a signal that looks like the following in the frequency ...
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1answer
26 views

Amplitude Demodulation using RC low-pass filter in matlab [closed]

I am working on an Amplitude modulation and Demodulation assignment, which has some required waveform. I am facing problems with demodulation. I have amdemod and ...
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15 views

Should S-Matrix components for scattering response in a Polarimetric Radar be Real or Complex?

I am trying to implement some polarimetric decomposition algorithms on my MIMO polarimetric radar. At first, I will try the Pauli Decomposition algo. But instead of doing signal processing on the ...
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19 views

Simple sample and reconstruction code - MATLAB

I am trying to go from theory to code. I take x (let say 16KHz is continuous time) then I sample it in 2Khz So I do ...
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1answer
25 views

How to extract pixel-specific time-stream from mp4 video

I am interested in extracting specific timechange information from an mp4 1900x1200 20fps video.The only pixels I want to process can be found in its borders. Therefore I only need to process ...
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0answers
20 views

Weibull fading channel

As explained here for Rayleigh fading channels, can anyone help me arrive at similar equations for finding fading gain ...
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1answer
28 views

how to extract pitch contour of a speech by matlab?

I am totally new in Matlab. Can anyone please explain in details how I can extract pitch contour of a speech? I would like to observe how the speaker's pitch varies during his speech to know whether ...
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25 views

FIR anti aliasing filter design

Suppose we have a signal with a $3\mathrm{kHz}$ bandwidth and a sampling rate of $48\mathrm{kHz}$. Then we want to decimate ($6$-rate decimator) it, in which the decimator has a passband ripple of ...
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1answer
36 views

Filter Design near Nyquist frequency (complex curve fitting)

I'm fitting IIR filters to a complex transfer function with Matlab's invfreqz.m. My fitting results are very good, but when I come very close to the Nyquist frequency the phase response runs to 0 and ...
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2answers
32 views

Finding Argmax in MATLAB [closed]

I have a Gaussian random variable $z$, whose mean $\mu$ and variance $\sigma^2$ are functions of two variables $x$ and $y$. Is there any way in MATLAB so that I can find the values of $x$ and $y$ for ...
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7 views

MATLAB: get members of histogram populations EXCLUDING those inbetween

The Problem I have a (noisy) square wave signal and need to extract the data points that make up the 'baseline' and 'plateau' ONLY. I do not want data from the rise and fall. So far I have ...
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2answers
39 views

detect to rising, stable and falling point in non-smooth rectangular wave

I am working on basic signal processing problems in MATLAB. I have found a signal from the internet (i don't remember the site exactly). The data is organized in column wise. 1st and 2nd column is ...
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38 views

plotting frequency response to window sinc funtion in matlab

I am taking DSP and the instructor explains theory, but has not shown a single example all semester. One problem on the current homework assignment is to plot the frequency response of a windowed sinc ...
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1answer
69 views

How to remove noise using mean and median filters?

I can remove the noise using moving average filter. The MATLAB code is shown bellow. But how can I remove the noise using mean and meadian filters?
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2answers
40 views

Pre-emphasis filter design

I am using the standard MATLAB filter function to design pre-emphasis filter. However, I am getting the wrong results back! I have the ground truth so I can check ...
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0answers
34 views

Similarity between RSSI data of two devices

I have collected the transmitted RSSI (Received Signal Strength Indicator) data of a base station by two different devices at a same time. I want to find out the similarity between them in MATLAB. Is ...
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1answer
41 views

how to detect short pause in a speech with noise?

I would like to count the number of short pauses in a speech and know the duration of the pauses by loading the signal into Matlab but I am very new to Matlab. Can anyone help and give me some ideas ...
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1answer
24 views

How to filter objects on basis of orientation of regionprops

I am trying to detect straight vertical lines in an image. I used vertical edge detection and then I tried to check which objects has the ...
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1answer
22 views

What is the default carrier frequency of matlab's pskmod?

I'm using the matlab function pskmod for modulating a bit string. What is the carrier frequency used by default by the function?
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1answer
52 views

Choosing correct filter parameters for IMU sensor datas

I have a IMU sensor breakoutboard using ITG3701, LSM303D LinkProduct. This involves accelerometer, gyroscope and magnetometer. I have connected the sensors to a Arduino and sending the datas to ...
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1answer
40 views

Shall a $1^{\rm st}$ order IIR filter include $x[n-1]$ term?

I have seen a $1^{\rm st}$ order IIR filter in the following form: $$y[n] = \alpha x[n] + (1 - \alpha) y[n - 1]$$ Such as: another post in this forum However, the filters generated by Matlab, such ...
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22 views

Calculating Time Delay between initial sound and its reflection [duplicate]

I have been researching into calculating distance using sound on an iphone 6. I have been playing short frequency sweeps on one iphone and recording the data on another phone sitting on top of the ...
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1answer
34 views

Calculating spectral coherence coefficient (scc) - implementation help

I am trying to calculate the SCC of a cyclostationary signal. I have estimated the Spectral Correlation Function (scf) of the signal using FFT Accumulation Method (FAM). I implemented the following ...
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26 views

How to use deconv() instead of roots() on MATLAB to find roots to a polynomial [closed]

I recently read that for polynomials of degree 5 or more, when executed with the roots() command on MATLAB produces an error. The documentation said as follows: As a substitute, using the deconv() ...
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35 views

How to specify 2-D coordinates of an object in matlab?

This is the scenario: I marked two axes (figure below) on a board and a camera(global vision system) sees the board. I want to make the vision system to recognize $X$ and $Y$ axes and specify ...
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7 views

A 2 input 1 output model with time delay

What assumptions should be taken into consideration if I need to build a 2 by 1 black box process model on Matlab where the inputs samples I have are sampled each minute to result eventually after 1 ...
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42 views

Unable to generate and verify a sound wave of frequency 200 Hz

I am trying to generate a sound that contains low frequency in the range 100-500 Hz. I then record the sound using a microphone and generate a spectrum for the recorded signal using ...
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0answers
13 views

Does MATLAB have a FM discriminator [closed]

I'm wondering if MATLAB communications or DSP toolboxes has a FM discriminator? If so, what is the name of the function/object?
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22 views

Approximation of Step Response from Data with delay

How can I approximate a Step Response curve from a measured data of a single input and a single output using Matlab while the delay between the input and the output is 30 minutes?
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37 views

What is signal to noise per sample?

We have heard about SNR. The ratio of signal power to noise power. As such we should calculate the powers of the signal and the noise and take the ratio of them. But in MATLAB documentation - in ...
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1answer
33 views

MRI Slice image reconstruction

I have an MRI K-Space data 320 x 320 x 256 x 8 (4D complex double) from < mridata.org > . The data represents 320 x 320 K-Space of 256 slices from 8 channels. I am trying to reconstruct images for ...
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1answer
51 views

how to detect two parallel lines in a binary image with MATLAB

I am working on license plate detection using hough transform. I am trying to detect the horizontal and vertical edges and then to find the parallel lines. My ...
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1answer
43 views

Signal's Fundamental Frequency is different from Plotted Signal

I've been attempting to plot the following function using MATLAB: $$ x(k)=\sum_{n=11}^{50} \sqrt{n} \sin (2n\pi k) +\sum_{n=1}^{40}\sqrt[3]{n} \sin (3n\pi k) $$ Note that $k$ is a continuous ...
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25 views

Gibbs energy in MRF

I am stucking in Gibbs energy in MRF. Firstly, let us define some definition Let $S = {(i, j)|1 ≤ i ≤ m, 1 ≤ j ≤ n}$ be the set of sites of a rectangular lattice for a 2D image of $m \times n$ ...