f0 standard deviation

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f0 standard deviation

Post by luigiV »

Hi Marc,
I would like to submit to you the problem affecting the Standard Deviation relative to the frequency of the H / V main peak.
I verified that with versions 3.0 and later there is a different value for average - minimum and average - maximum both considering f0 from windows and f0 from temporary window that appears on the H / V plot results.
When processing data files with Geopsy releases before 3.0 this does not happen.
Is there an explanation for this discrepancy? Is this a false problem?
I am attaching a pdf related to the processing of the same curve with 2.10 and 3.4.2 releases where this problem is evident.

Best regards
Geopsy comparison.pdf
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Re: f0 standard deviation

Post by admin »

Hi Luigi,

I'm not surprised that some minor differences exist. Since 2.10, many details changed (sampling, smoothing, rounding of number of samples to basic prime numbers for FFTW speed-up, geometric average for amplitudes,...). For your example, this is about 2% difference for the estimation of f0 range. I'm unsure if I did a complete comparison between 2.5.0 and 3.x.x for H/V. For sure I did it for linear FK, and there are minor differences that can be fully explained by the minor modification cited here above.

Best regards,

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