# Tag Info

### What does hue, saturation and intensity means in image processing?

To display a color image, each pixel needs to have those three values: Red, Green, and Blue. Sometimes there is a fourth, Alpha, channel, but let's ignore that for this question. What you're seeing in ...
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1 vote

### Is it ok to use MATLAB ''freqs" command for Digital filters?

You should use freqz to calculate frequency response of a digital filter and freqs for an analog filter. Given a transfer ...
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### Is it ok to use MATLAB ''freqs" command for Digital filters?

For discrete-time filters, such as FIR and IIR filters, the appropriate Matlab function is freqz.m. You need to evaluate the frequency response on the unit circle of the complex plane; ...
• 80.2k
Accepted

### Matlab Filter Designer "Filter Information" shows wrong order

Matlab is correct. A causal FIR filter with transfer function $$H(z)=\sum_{n=0}^{N}h[n]z^{-n}\tag{1}$$ has filter order $N$ only if $h[N]\neq 0$. If $h[N]=0$, the transfer function $(1)$ can be ...
• 80.2k
1 vote
Accepted

### Multiplication in frequency domain for a signal containing a whole frequency spectrum

Multiplication in the frequency domain is equivalent to convolution in the time domain. When the signal occupies multiple frequencies, describe the signal in the frequency domain and then do the ...
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### Calibration using Camera Calibration Toolbox for Matlab vs OpenCV

The main reason you are not getting similar results is that you've used different camera models. With OpenCV you are using the highest order radial distortion coefficient k3 while it was excluded (...
• 146

### What is the proper way to implement a real time spectrogram?

It actually depends on what you are trying to achieve. I have two general points here to help you: First, you need to know the specifications of your real-time system. How long do you need to update ...
• 129
Accepted

### How to decode a MIMO stream using V-BLAST?

In V-BLAST, $y_{ki}$ is a scalar (that is, a complex number). It is the (equalized) symbol transmitted by antenna $k_i$, with noise. Keep in mind that all vectors are column vectors ($n \times 1$). ...
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### Confusion regarding frequency spectrum in MATLAB

The $fs$ you are getting from audioread is the sampling rate and has nothing to do with the actual frequency content of the signal you are analyzing other than the maximum frequency would be $fs/2$. ...
• 2,686
1 vote

### How to exclude diffuse moving features in a stack of images

It seems that the «artifacts» roll vertically at constant speed? I wonder if that could be exploited somehow. I.e. a signal model consisting of desired signal + uncorrelated noise + «slow innovation, ...
• 2,186
Accepted

### How to exclude diffuse moving features in a stack of images

So I tried Gillespie's suggestion of TV. First, I got the individual frames from your GIF out using ffmpeg: ...
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### How to exclude diffuse moving features in a stack of images

Assuming there is no underlying data-specific mechanism that can be exploited, I think your best bet would be Total Variation Denoising. It reduces noise by minimizing the variance of the data, ...
• 503
Accepted

### How to generate a raised-cosine window with a specific roll-off factor in Matlab?

You want to generate a raised-cosine window to do, x .* w, instead of upsampling/filtering as is shown in the Matlab documentation. The trick to know about ...
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### How to generate a raised-cosine window with a specific roll-off factor in Matlab?

@F105 I'm not sure what you mean by "to make the sides of the window steeper", but MATLAB's 'rcosdesign()' command should do what you want. Perhaps experimenting with the following code will ...
• 4,818