fastlib / fCWT

The fast Continuous Wavelet Transform (fCWT) is a library for fast calculation of CWT.
Apache License 2.0
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Dose it can be used for real-time application in processing low frequency signal? #56

Open GUIMINLONG opened 9 months ago

GUIMINLONG commented 9 months ago

First, I would like to express my sincere gratitude and respect for the contributions of the authors of this project.

Below is my question.

When I tried to use the output of fcwt input to my model, I found that to obtain a clear spectrum on low frequency, the signal input to fcwt should long enough. For example, if the target frequency is 20 Hz, the duration of the input signal should larger than 1/20Hz=0.05 s. Otherwise, lower frequency spectrum will blur. Dose this means that the conflict between frequency resolution and time resolution still exist?

Or is that mean, for the processing low frequency(f) signal, the input segment duration delta_t should always satisfy that delta_t>1/f. And the high efficient of fcwt only ensure real time processing of with frequency satisfy f>1/delta_t. (Because Heisenberg uncertainty principle?). From what I know, one of the advantage of cwt above stft is it high frequency resolution at low frequency, if limitation of Heisenberg uncertainty still hold, what the advantage of fcwt above stft for real-time using, especially for the processing of low frequency signal.

My question may seems weird, but it is what confuse me now. Any one familiar with are welcome to share your opinion.