David Wurtz
  • Member for 7 years, 2 months
  • Last seen more than a month ago
Convex Optimization in Signal and Image Processing
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6 votes

There's a whole area of signal processing dedicated to optimal filtering. In pretty much every case I've seen the filtering problem is formulated with a convex cost function. Here's a freely ...

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Proof from wave equation of upper limit of active noise cancellation
2 votes

I don't have a mathematical proof for you, but here are 2 issues to think about. The impulse response from the actuator (speaker) to the error measurement (microphone) is non-minimum phase. This is ...

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Processing Accelerometer Vibration Data With FFT
2 votes

This is just a guess, but it could be that you are getting these harmonics because you have inadequate acoustic coupling between the accelerometer and its mount point (i.e. tape isn't secure enough). ...

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Why is my discretized transfer function unstable when my discretized state-space model is stable?
2 votes

You're using a high order model so you might be running into numerical precision issues. Make sure the realization of model_state_space is minimal. You can do this with min_model_state_space = ...

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How to find peaks and periods?
1 votes

You could try a Savitzky-Golay filter, followed by standard peak detection. The S-G filter will preserve the location of your peaks. If you're using Matlab it comes with the signal processing toolbox. ...

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Designing High Pass Filter to Remove DC Offset from a Signal
1 votes

The way you wrote it, 1/f0 defines the -3dB cutoff frequency. This is easy to see if you let s = 1/f0. The numerator becomes 1 and the denominator becomes 2. A gain of 1/2 is -3dB. Since it's high-...

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Why do eigenvectors specify the direction of fastest and slowest changes in the image
1 votes

The eigenvector corresponding to the largest eigenvalue of the autocorrelation matrix indicates the direction of fastest change, while the eigenvector of the smallest eigenvalue indicates the ...

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Detecting changes between two similar images
1 votes

If I were to approach the problem here's what I might try... convert the images to greyscale as Andrey suggested, look at the normalized cross-correlation on a subregion of the images to find the ...

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Is there a widely available implementation of an adaptive, recursive, numerically stable IIR filter?
1 votes

The equation error approach should have worked (assuming your model was the same order as the unknown system). While it's not as efficient as QRD-RLS algorithms you can always use a Kalman filter to ...

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Expected value of coupled signals is zero
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0 votes

It means u and v are orthogonal. If u or v or both have zero mean then they are also uncorrelated. If they are uncorrelated and jointly gaussian then they are also independent.

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fundamental question regarding bandwidth
0 votes

It's not a single frequency. You also have sidebands.

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Is there any tool to anlyze audio specturm of a song and give the average visually ?
-1 votes

Audacity will let you look at a song's spectrum/spectrogram, and it works with most audio formats. It's also free!

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