instruction stringlengths 31 27k |
|---|
I am using the FFT to calculate the amplitude and phase of AC cos signal. Regarding amplitude it gives me an accurate result but I get wrong result for a phase: 6 degrees instead of 36 degrees.
My MATLAB code is as follows:
fs=3840; % sampling frequency
N=64; % number of sample
f=60; ... |
In framing of audio samples' in audio feature extraction, what is need of frame shift while giving frame size??
i.e. frame size = 20ms,
frame shift = 10ms.
Rather then shifting/overlapping why can't we use continuous frames then of overlapped??
|
I've already asked this question on SO, but didn't get an answer, I tqake a shot here.
I am trying to get the PSD of a real data set by making use of fftw3 library
To test I wrote a small program as shown below ,that generates the a signal which follows sinusoidal function
#include <stdio.h>
#include <math.h>
#define... |
There are many descriptions of how to turn a 2D image into a 3D one, however I want to do the opposite, in particular to a ball. As an example, consider the following ball:
If only the (relatively) slow change in intensity due to the light could be removed, the ball would look 2D.
My first approach was to try get a l... |
I'm currently studying the Z-transform, and I'm having issues in understanding the time shift and differentiation properties, to be precise: calculating a Z-transform explicitly, and obtaining it by using those properties yields different results.
For example, a common Z-transform is the transform of the discrete unit ... |
I have random variables $X_1, X_2, \cdots, X_m $, which can take $n$ values and is distributed iid according to $\Theta=(\theta_1, \theta_2, \cdots, \theta_n)$. That is $X_k$ can take values $\{1,2,\cdots,n\}$ and $P(X_k=i)=\theta_i, \ 1\leq k \leq m, \ 1 \leq i \leq n$.
I observe a random variables $Y_1, Y_2, \cdots, ... |
What is best practice/algorithms to remove static noise from speech ? static noise aka Stationary Signal/static noise due to
1.humming sound due to of telephonic line/channel,
2.moving Vehicle,or due to
3.constant noise of fan or other nearby instrument .
|
I have a $512$ sample frame, lets call it X. The frame is further divided into four sub-frames of $128$ samples each. Each of these sub-frames have a different frequency.
For STFT, I use MATLAB's gausswin(N) function where N is equal to $128$ in my case to generate a Gaussian window, let's call it W. I zero-pad my win... |
I don't understand what happened in my simulation.
I would like to perform a trade off between 2 ways to estimate power in frequency bands. I want to detect spurious frequencies.
First method:
I constructed a vector of noise and computed the periodogram without
windowing. As example, for a vector length of 1048576 a... |
I am new to the study of time series. Recently I have asked a question about the covariance of real and imaginary part of a real(in time domain) stochastic time series and I have received an answer for it. The problem is that for continuous time series the variance of each point in frequency domain is infinite. I've b... |
This is my understanding of 'energy compaction' and want to know if it is right. Take a vector. The energy of the vector is the sum of the squares of its elements. If A is the transformation matrix that is unitary, it can be proved that the energy in x and Ax are same. Energy conservation property. Energy compacti... |
How an algorithm can be developed to count numbers and bolts in the image below.
|
Does anybody know why we need 2 different tone signals: one high frequency and one low frequency to create a tone burst in Dual-Tone Multi Frequency signalling?
For example, to create a tone burst of 3, we need a high frequency $1477 \mathtt{Hz}$ and a low frequency $697 \mathtt{Hz}$. Does anyone know the reason for th... |
Like energy compaction transforms, the inverse transforms like IDCT are energy spreading transforms?
|
The example that I've seen on state estimation involves deriving the ABCD matrix of a physical system (i.e. falling object) and tracking that object.
I would like to use Kalman Filter for signal denoising applications (specifically EEG signal). How could I apply KF in this situation since ABCD matrix cannot be derived ... |
Is it common to find systems having signal to noise ratio (SNR) less than 1 i.e. noise is more than signal? I am currently working with SNR of -5db to -20db. And how useful is it to work with sensor readings having negative SNR? I am asking it because the algorithm I am using to solve a problem works well with negative... |
In Oppenheim's "discrete time signal processing", it says,
How is the equation (10.65) derived?
PS:
you may try to derive it with Fourier transform of the original and the sampled signals.
But i think it is not appropriate.
Because when you are considering about the PSD of a signal, the assumption will be the fourier ... |
After filtering my noisy input signal using an anti-aliasing and FIR filter, I now wish to get the basic signal information (peak voltage and impedance; $R$ and $X$) from the pre-filtered as well as the post filtered signal.
A method to find the peak value that was strongly recommended to me was, Fourier Full Cycle Al... |
I stumble quite often upon the notion that two or more parts of a signal are correlated to describe semi-formally that they belong together. For example in image processing, two pixels on an edge feature tend to be correlated whereas two adjacent parts of a 3D structure that represents water droplets in a particle simu... |
Given a signal with zero mean and a standard deviation of 0.1 sampled at 5000 Hz.
What would be the Standard Deviation of its 1st, 2nd and 'n' derivative?
For instance, let's say we measure the distance to a constant range target.
The STD of the sensor measurements of the range is 0.1 [Meter] (Assume the error is white... |
Regarding extraction of MFCC from speech signal...
I have checked for the detailed procedure of extraction of MFCC from http://practicalcryptography.com/miscellaneous/machine-learning/guide-mel-frequency-cepstral-coefficients-mfccs/
For each frame they have extracted the features..
If the signal consists of 100 frames.... |
I am trying to train a cascade object detector in MATLAB using the built in functionality from the Computer Vision Toolbox.
I’ve taken 500 photo’s of the sole of my shoe. Every photo is taken from the same angle, so there is very little shifting in rotation and scaling from all of the images.
For the negative images I... |
How would you describe this signal? It's like a sinusoid but as if its frequency was constantly increasing: could you write down a mathematical description? Thanks. And no, this is not homework...
|
I am working on a project to compare images in the database. I use color and gradient orientation as features of the image and these features are not rotation invariance, therefore to compare well I proposed to warp the images using 5 parameter affine transformation and optimise the 5 parameters to obtain the best mat... |
I am calculating the average power of a vector. I would like to compare the final expression with the simulation. However, they are not equal. Please help me to point out which steps are wrong. Thank you very much.
Calculate the average power of a vector:
$x(n) = \sum\limits_{i = 1}^{L - 1} {\sum\limits_{l = 0}^{L - 1... |
I am research about correlation kernel and I have some questions that need your help. Let see the pp. 3302-3303 in the paper:
Changyang Li, et al., Robust Model for Segmenting Images With/Without Intensity Inhomogeneities
The special kernel is defined as:
$$W(|y-x|)=\dfrac{\gamma}{1+\dfrac{1}{\sqrt{2\pi\omega^2}}e^{\... |
Given a camera, permanently located at the same position, angle and distance from what is being captured, and a single calibration image ( a row of vertical lines [ | | | | ] ), how would one go about using the image to apply correction (barrel distortion) to all subsequent images?
Numerous examples exist online for th... |
After clustering in image, I want to visualize the result. To do so, I first reshape an RGB image to 3*size.
The result of BSMC is the set of indices after clustering. So I change the value at the pixel. But the result is not what I wanted.
How to show correctly segmentation result?
X = imread('image3.jpg');
%X = imres... |
I need to design a filter to reduce noise from accelerometer readings and use this data to a control system. One of the problems of a simple low-pass filter (like a single pole IIR filter) is the delay introduced by the filter. As an alternative I saw many people using a kalman filter or a median filter. I'm very inter... |
I need to draw an outline of text in an image. Consider the below image as an example.
Can anyone suggest me a direction to achieve this? I don't have experience in image processing. Any tools/lib or anything that can generate this kind of image will be helpful.
|
Is there any difference between the terms sample and sample value in DSP? In statistics, those are very different concepts: a sample is a subset of a population: it is a set of random variables. A sample value is the realization (aka. observed value) of this set.
In DSP, I feel that sample is often used with the same ... |
For a visual regression test I need to compare screenshots of webpages (different release-versions). I started with pixel by pixel compare. Actually I split the screenshot in different parts (maybe 10x10 rectangles) and compare the histograms of correspondending parts.
Now I try to find an approach to find regions of i... |
Ok, so suppose I've got a phone with gyroscope, compass and 3-d accelerometer.
I wanted to track position of the moving phone for about 1 minute with let's say 50 mm accuracy. Actually let's say that I wan't to create some sort of pedometer.
Is this possible?
I already know that the signal from accelerometer is too noi... |
This is my testing image, it is taken from the paper Image Restoration for Linear Local Motion-Blur Based on Cepstrum:
I tried to transform it into its real cepstrum domain with this simple MATLAB code:
cepstrum_img=ifft2(log(1+abs(fft2(img(:,:,1)))));
imshow((abs(cepstrum_img)))
But my result is very weird: The maxi... |
A little background: I have an FPGA (running at 200MHz) that I am creating multipath events using buffers, all of that works. I take RF, mix down to IF, sample, make adjustments, out the DAC, and back up to RF. I use a windowed-sinc algorithm (like described here).
To do fractional delays, I compute the coefficient... |
This is just an outline of what I did (assume that all my dimensions fit):
(code that imports audio to read audio as function x)
X=fft(x);
(code to define time t and frequency f)
H=L+M*exp(-1i*2*pi*f*N)+O*exp(-1i*2*pi*f*P);
% This is where it gets tricky
% In the frequency domain I have the fu... |
Suppose I want to encrypt the voice data before sending using a ham radio, for example this unit.
Assume the encryption is simply AES encryption/decryption using predefined fixed key.
I am thinking of the following implementation:
1) Between the radio's transmitter/receiver and its logic unit, I'll place my circuit.
2)... |
in beamforming literature, people generally quote the following as a starting point:
$y(k) = \sum_{i} w_i^*\cdot x_i(k)$
Here:
i varies from 1 to N where N is the number of sensors
$w_i^*$ is the complex conjugate of the ith weight vector
$x_i(k)$ is the kth sample received at the ith sensor
y(k) is the output of the ... |
The detail-preserving upsampling algorithm in Photoshop CC is truly amazing. It can upscale any image while preserving details in almost real-time. And I truly wonder how it is implemented.
I've started by searching papers with keywords single image super resolution. And seems the current state-of-art algorithms requir... |
I have recently taken up studying compressive sensing related papers. Some things are not very clear to me or may be I am not able to visualize the scenario as is said. Like how $l_0$ norm minimization is NP hard? Can somebody explain with an example (step by step example may be?) of a matrix and vector for an equation... |
We know that a convolution can be replaced by a multiplication with a Toeplitz / Circulant Matrix. Meaning, assume I have convolution kernel $ h $ and matrix $ I $ (Of size $ m \times m $ for example), then there is a matrix $ H $ of size $ m^2 \times m^2 $ such that $ h \ast I $ is the same as $ H I^{cs} $ Where cs fo... |
Is there a library written in C/C++ that offers functions like QPSK modulation?
|
I have implemented a 2D->3D point triangulation method, which uses 2 poses P1 and P2 and 2 points back-projected to z=1 point1 and point2 to recover depth:
Matx14d A1 = point1(0) * P1.row(2) - P1.row(0),
A2 = point1(1) * P1.row(2) - P1.row(1),
A3 = point2(0) * P2.row(2) - P2.row(0),
A4 = point2(... |
I need measure timing of an signal that is send through a noise band limited channel (wireless).
By measure timing, I mean measure as exactly as possible when the signal has arrived at the receiver.
My idea is to use a matched filter (correlator) to match some symbol send by the transmitter and then locate the maximum... |
In the bag of words model, generally is it better to have more codewords or less? For example, if I have 1000 x 20 raw features, then what would be good value for codebooks? I am thinking of smaller size codebook ( such as 20) so that it forces the representation to be sparse.
|
Is there a way to compute the main lobe width of windows of the generalized Hamming window family (i.e. Hann, Hamming, etc.)? By main lobe I mean the first zeros left and right of the center of the Fourier transform of the windows.
I could not find any derivation in any of the standard textbooks. In Oppenheim/Schafer '... |
I know that for the Hough Transform to work on an image, it needs to be a binary image. To convert from a grayscale image, an edge detection algorithm should be employed. I notice that people always use Canny edge detection instead of others (e.g., Sobel). Why is that?
|
I'm a programmer/engineer that is getting into developing prototype wearable technology. I would like to be in a position to interpret raw accelerometer data and categorised the data into activities like running/walking/rest, etc.
The building and coding of the hardware and software is relatively straight forward, but ... |
I am building a morse code decoder in Python. I am using SciPy and Numpy for FFT, filter, etc. It is coming along ok, but the signal is noisy. I am extracting the dominant frequency from the FFT of the input signal (which is audio from a wav file), and sampling at a rate great enough to detect whether a signal is pr... |
I plan to calculate a signal's phase using Goertzel Algorithm. I have 2 signals coming to microcontroller's ADC. Need to measure the phase difference between them. Signals are 15MHz sinusoids. Sample rate will be about 1MHz or lower. Is it possible to use Goertzel with under-sampling? It would be much easier than calcu... |
If I want to amplify a certain frequency in a digital signal, can I just take the FFT, increase the real part of the value for the frequency I want (leaving the imaginary part alone), and then take the inverse FFT? I am wanting to do this to increase the frequency at which tones are detected, for a Morse code decoder.... |
I'm taking a multidimensional discrete cosine transform (FFTW_REDFT11) in FFTW, and am unsure how to compute the scaling factor. According to the documentation, taking the forward and reverse transforms results in the original image multiplied by a scaling factor:
[C]omputing a transform followed by its inverse yield... |
I am trying to decode Morse code from an audio (wav) file. Here is the technique I am using to detect the presence of the signal:
I have a window of size (sampling_freq/tone), where tone is the frequency of the Morse code tone, as determined by the fft (most prominent tone). I move this window across the entire recor... |
I want to design a high pass filter (f0*S/1+f0*S) in order to remove the dc offset from a signal ? (i.e. how to choose the frequency f0).
Thanks,
Hacene
Ps : the filter is for MATLAB implementation, this is why i would like to have it in continuous time.
|
I am trying to teach myself some signal processing and control theory. I'm currently working through THIS tutorial. I've started an ipython notebook to keep my notes in.
Unfortunately, something is wrong with my very first simulation of a simple first-order low pass filter. The differential equation is
$$\dot{x} = \ome... |
I have an image that includes object and background. However, the object appears some inhomogeneity region due to illumination. My work is that how to detect inhomogeneity region. Which is feature can represent it? Example: low inhomogeneity-high/low feature value....Thank you so much
or
|
I've just learned that the A/D converter I am using is not sampling at my desired sampling rate. I request 20 seconds of data at 1920Hz and I receive 38400 points of data that were actually sampled at 1920.93Hz.
So for example, if I sample a 30Hz sine wave and chop the signal up into 300 sections, the phase of the s... |
I have come up with a new descriptor(floating point). I want to evaluate this descriptor against SIFT, GLOH, etc etc. I am using the K. Mikolajczyk, C. Schmid, approach. The method is described in the link http://www.robots.ox.ac.uk/~vgg/research/affine/descriptors.html. They have provided the binaries and the data se... |
I've need to remove a DPL/DCS signal from a recording. Roughly speaking, a DCS signal is a low frequency (67.15Hz) square wave sent at the same time, over the same carrier, as speech. Because it is a square wave, it has many strong harmonics that overlap with speech. Obviously, the speech must be preserved.
On the surf... |
I am studying on the implementation of a continuous stream OFDM baseband modem. Googling and also searching here on stackexchange for synchronization techniques I found the descriptions of several existing algorithms, depending on the specific system features, but no detailed implementation of a time-frequency synchron... |
A plot showing two S21 peaks through a resonator is given below:
As you can see, the first resonance peak occurs at 4.43GHz. The fit applied to this peak is given below.
$$y = A - 10 \log_{10} {\left[ 1.0 + \left( 4Q^2 \left(1-\frac{\omega_d}{\omega_0}\right)^2\right) \right]}$$
This fit gives a nice curve and physica... |
In The GIMP, and also in photoshop, you have the DODGE/BURN tool to enhance colors in shaded or highlighted regions, which would otherwise be blackish or whiteish. I found empirically that this filter is a good preprocessing step for a computer vision task I am implementing.
I found in Andy Finnell - How to implement d... |
I am extracting a property of a signal which I represent with either a 0 for absent or 1 for present. This property is extracted for each data point in a time series and in the end I am left with a binary sequence for each signal. These sequences are somewhat similar, since their origin is related, but they are differe... |
I have read in all books that:
Impulse(n) = 1 when n=0 , 0 otherwise
So when we state impulse response of signal x(n) I do not understand what is its actual meaning -
Does it means that for n=1,2,3,4... value of :
x(n) . Impulse(0)
Hence in that case if n >= 0 we would always get y(n)(output) as x(n) as:
x(n) . Impul... |
I am reading a paper, in which the author defines gabor kernels as :
$$
\psi_{\mu,\nu}(x,y)=\frac{\lVert \mathbf{k}_{\mu,\nu} \rVert}{\sigma^{2}}\exp \left(-\frac{\lVert \mathbf{k}_{\mu,\nu}\rVert^{2}\lVert \mathbf{z}\rVert^{2}}{2\sigma^{2}}\right)\times\left[\exp\left(i\mathbf{k}_{\mu,\nu}^{T}\mathbf{z}\right)-\exp\le... |
It seems to be reasonably well accepted that Sigma-Delta ADCs have much looser requirements for the anti-aliasing filter due to both the noise shaping and high modulation frequency.
However, it seems to implicitly assume that the input signal is continually sampled by the converter. Many sigma-delta ADCs such as the T... |
I'm trying to write a C program that can get the PSD of an recorded audio file, I'm using for the fftw3 library. I wrote a program that calculate the PSD so far only for sinus function, but the result is correct, my problem is that I have some trouble to use the windowing method on my data.
Let's say that the audio fil... |
I am trying to listen VLF radio signals. I have a recorded wave file (download) and here is the frequency spectrum:
I have produced this spectrum using this matlab code:
signal= wavread('/Users/ecabuk/Downloads/DR0000_0165.wav');
X_mags = abs(fft(signal));
bin_vals = [0 : N-1];
fax_Hz = bin_vals*fs/N;
N_2 = ceil(N/2);... |
I know all about conversion of frequency from HZ to normalized frequency and from normalized frequency to angular frequency ,but I wonder how it is done in MATLAB.
I have the following code:
f:0:0.001:1;
omega=pi*f
here f=normalized frequency and omega=angular frequency. My question is how do we get the interval value... |
I am using YIN algorithm in a school project of mine which uses pitch detection on guitar sound. I when I play a note I get random frequencies at the beginning until they stabilize. I am thinking those are probably from action of pick on the strings.
I am going through the original paper:
Cheveigne A, Kawahara H. - ... |
I am trying to generate a AWGN waveform to add it to the signal of my simulated communication system. The operating bandwidth of the communication system is about B=3GHz and suppose that T=300K (my signal is comprised of very short pulses, I am simulating an IR-UWB system).
What I have done so far is:
N = k*T*B
sigma =... |
Learning
Informative
Statistics:
A
Nonparametric
Approach paper presents an approach to parameter estimation by entropy minimization. There are other related works "Minimum-entropy estimation in semi-parametric models" download link ( http://dl.acm.org/citation.cfm?id=1195853). The rationale provided is that minimiza... |
What is the method for generating coefficients for the Farrow structure in Matlab? I am designing a low pass filter using firpm, but the output of the Farrow structure is not delayed.
|
I'm a physics Phd student and just have a self-taught knowledge about lti-systems. After a while I found out that several techniques such as heat capacity or thermal-conductance measurements can be modeled as lti-systems. The current approach to estimate the physical quantities is a nonlinear fit of the solution of the... |
I have 10 images in the folder say "D:\images\" named as frame1,frame2,...,frame10. I want to make a movie from the color images with frame rate as per choice.Also i want to save created video file in .mp4 format at the location "D:\video\".
Is it possible to do so in MATLAB?how?
|
I'm giving a lecture on LTI systems. I encountered some questions:
for a discrete LTI system H with impulse response h, is the system applied on signal x(t) equals x*h - normal discrete convolution or the cyclic convolution?
can you please give me some examples of useful LTI systems? such as Prewitt or Roberts edge de... |
suppose I know the frequency response of a (linear) model approximating a real physical system but only at a specific frequency $f_0$ (so basically I have a complex number whose module is the magnitude response and the phase is the phase response).
In Matlab I want to filter a sinusoidal signal whose frequency is $f_0$... |
What does mutual information (MI) convey? If 2 signals are independent then MI is zero; What does this imply and mean in the case of mutual information of error, and in general definition of MI and entropy.
What is the interpretation if MI of error is decreasing or getting minimized?
|
Ideally, a gyroscope and an accelerometer would be enough for a complete navigation solution (attitude + position), using dead reckoning. This comprise the Inertial Navigation System, INS. In non-ideal world, we would couple the INS with GPS. The GPS helps 'fix' the navigation solution at certain times, to help mitigat... |
I'm looking for info that would help me to build a Tape Saturation process.
I'm working with the WebAudio API. The API provides a number of DSP nodes that perform basic processes, such as a Convolver node and a WaveShaper node. The WaveShaper seems to suggest it is designed for distortion effects (http://www.w3.org/TR/... |
I'm working on a project at my university and it involves background noise recognition/classification. I'm very new to this so I'm unsure what to really search/google or where to really begin any research.
I'd like to remove background noise from any audio file and analyze THAT and not the primary signal (for exampl... |
I know the FIR approach, I have seen IIR, to, but I'd like to know if it's possible to implement a Hilbert transformer in analog domain, i.e. with integrators instead of delays. Is it possible? If yes, how?
[edit]
After some searching on my own, I stumbled upon an answer in sci.electronics.design - "Analog delay??" (I... |
I was maximising a likelihood function, which is convex. I know that the system has a K-sparse solution. I wanted to know the conditions (or some sufficient conditions) on the likelihood function under which l1-regularisation is guaranteed to give me the sparse solution.
In other words, I am trying to solve the followi... |
I'm following a tutorial about the FFT. It's well explained but I don't understand the meaning of the frequency vector:
Fs = 150; % Sampling frequency
t = 0:1/Fs:1; % Time vector of 1 second
f = 5; % Create a sine wave of f Hz.
x = sin(2*pi*t*f);
nfft = 1024; % Length of FFT
% Take fft, padding with zeros so that le... |
How we can track a single selected object from multiple detected moving objects using single fixed camara?
|
Here is my signal
Cos(n/2)*cos(pi*n/4)
cos(n/2) has period 4pi and cos(pi*n/4) has period 8
Now, the question is will the signal be periodic for fundamental period 32pi ?
|
I'm generating a sinus by using a lut method on a DSPic33f. My sample rate is 48 kHz, so I saved 12000 of the first value (unsigned int, 16 bits) and use trigonometric formulas to calculate the other parts of the sinusoid. I can change the frequency of this sine by turning a rotary encoder. Every 2 ms, a timer interrup... |
I have a non realtime application where I need to run a bandpass FFT filter on a data array of between 5k and 10k data points. Do I break it up into (say) 256 point chunks, run the FFT on that and simply move onto the next 256 items, or is that too naive?
|
Say you have a linear chirp, which is a bit like a sinusoid with a gradually increasing period, but instead of the linearly increasing period, could you pick an arbitrary value, like the red line in the image below?
How would you write the definition of this? Say that the period variable is called AP (arbitrary period... |
I obtain the cross power spectra by the following steps:
compute the FFT of signal A and B
Multiply A with the conjugate of B store it in C (cross power spectra)
Now looking at the Phase of this cross power spectra C, what all information can I deduce about the two signals A and B?
|
I have quite a few noisy signals and I want to calculate their spectral tilt over time, preferably using a method from literature. So far, I can only come up with the slope of the line between the F0 and F1 peaks. The problem is, I don't know how to calculate the spectral tilt by hand for the below example (which is a ... |
I have found the definition of the following formulas in a paper regarding active vibration control, where they are called sine and cosine modulated integrals.
$y$ is measurement signal with a strong periodic component of frequency $N\Omega$
$$y^{(i)}_{Nc}=\frac{2}{T}\int^{T}_{0}y^{(i)}(ϕ)\cos(Nϕ)dϕ$$
$$y^{(i)}_{Ns}=\f... |
I would like to write a DFT program using FFT. This is actually used for very large matrix-vector multiplication (10^8 * 10^8), which is simplified to a vector-to-vector convolution, and further reduced to a Discrete Fourier Transform.
May I ask whether DFT is accurate? Because the matrix has all discrete binary elemen... |
I have to calculate asymptotic coding gain with soft decision decoding over an uncoded reference system. Lets say the coded system requires a bandwidth $k$ times higher than the bandwidth of the uncoded system. Does the variance of the white additive Gausian noise of the coded system is $k$ times the variance of the s... |
I currently work in a project of clinical software (C#) which deals with clinical biosignals, specifically EMG and other low-frequency signals (load-cells, goniometers, and other biomechanical instruments).
We have to be able to:
Create filters based on cuttoff frequencies (low and high) and filter order, for a given ... |
While learning Fourier series I read the definitions of representation for a continuous time signal $x(t)$ as:
$$x(t)=A_0 + 2 \sum_{k=1}^{\infty} A_k \cos(k \omega_0 t) - B_k \sin(k \omega_0 t) \tag{1}$$
where $A_k$ and $B_k$ are real.
Another definition was:
$$x(t)=a_0 + \sum_{k=1}^{\infty} a_k \cos(k \omega_0 t) + ... |
In image processing, we have two kinds of major kernels that are average kernel and Gaussian kernel. For image segmentation, which is difference between average kernel and Gaussian kernel? I found some paper said that they are similar, and average kernel implement faster than Gaussian kernel, right?When we use average ... |
I have a bandpass signal centered at 2 MHz and bandwidth of 50 kHz (the signal frequency varies from 2 MHz - 25 kHz to 2 MHz + 25 kHz). This signal is being sampled at 10 MHz.
I want a frequency resolution of 100 Hz in FFT.
I want to know:
How many samples of the signal should I take to achieve this frequency resoluti... |
I'm studying a book about DSP and trying to make exercises. Here is one I'm interested in:
A scientist acquires 65,536 samples from an experiment at a sampling rate
of 1 MHz. He knows that the signal contains a sinusoid at 100 kHz. He
needs to determine is if there is a second sinusoid at 103 kHz. As a start,
he tak... |
I am looking for a kernel acting as a low pass filter that satisfies these conditions:
$$K(-\mathbf{u})=K(\mathbf{u}) \tag{1}$$
$$K(\mathbf{u}) \ge K(\mathbf{v}), \;\; \text{if} \;\; |\mathbf{u}|<|\mathbf{v}|, \;\; \text{and} \;\; \lim_{|\mathbf{u}|\rightarrow\infty} K(\mathbf{u})=0 \tag{2}$$
$$\int K(\mathbf{x})d\mat... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.