Cat meow sounds visualized with auto-correlation function

Re:Cat meow sounds visualized with auto-correlation function by hereforphone on Friday December 10, 2021 @02:46PM (#29514621)

ACF has a lag argument correct? Also isn't the bright vertical line just the result of the fact that ACF at lag 0 is 1?

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Re:Cat meow sounds visualized with auto-correlation function by gbh444g on Friday December 10, 2021 @11:13PM (#29518354)

It does, but ACF[X] at 0 is the sum of X[i] squares, so when sound gets louder, ACF at 0 also gets higher.

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Re:Cat meow sounds visualized with auto-correlation function by hereforphone on Saturday December 11, 2021 @11:54AM (#29522286)

You're probably sick of this conversation by now :). But at least in radio applications I think that acf[0] is normalized so that it's 1 (typically). And again the ACF is calculated at several lag arguments and the sum is used to build the final graph / array.

But you obviously know more about this than me, I'm just putting out what I know. Your paragraph above, I actually copied so I can study it a few times. So thanks.

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Re:Cat meow sounds visualized with auto-correlation function by gbh444g on Sunday December 12, 2021 @10:57PM (#29536441)

It sounds this is what I'm doing: taking ACF at equally spaced offsets. Not sure what the sum of ACFs would achieve, but this might turn out a good idea.

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