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Re:Sharpened Cosine Distance as an Alternative for Convolutions by jschveibinz on Friday July 22, 2022 @11:56AM (#32193392)
Interesting. However, a matched filter is the optimum detector wrt maximizing SNR of the output signal (the features).

https://www.sciencedirect.com/topics/engineering/matched-fil...

https://en.m.wikipedia.org/wiki/Matched_filter

I wonder if this technique has been tested in “noisy” signal environments? Or is this just useful in infinite SNR applications?

Re:Sharpened Cosine Distance as an Alternative for Convolutions by gnramires on Friday July 22, 2022 @04:00PM (#32196447)
I tend to think of a matched filter as an "optimum denoiser" (in the mean squared error sense with white gaussian noise), but it's not an optimum detector in the general case, or an optimum "de-interferer".

The case shown here should be more resilient to changes in signal amplitude and non-matching interference.

Of course, because the kernel is actually learned, it can adapt to interference and try to be a "matched filter to what we want, plus anti-matched filter to interference" (i.e. give near-0 response to common interference signals). But SCS does seem like a more natural way to achieve a similarity metric and feature detection. (although this non-flexibility might work against it)

Re:Sharpened Cosine Distance as an Alternative for Convolutions by krapht on Friday July 22, 2022 @12:45PM (#32194093)
optimal among linear functions, and the noise is gaussian...

of course noise is not gaussian in many interesting applications and nothing is stopping a nonlinear function from getting better results than a matched filter, we just have no theory to discover what such a function would be

so yes, like you, i'd need to see results on actual data before spending time to learn more about it...

Re:Sharpened Cosine Distance as an Alternative for Convolutions by fxtentacle on Friday July 22, 2022 @01:19PM (#32194537)
In my opinion, this looks promising:

https://github.com/stevenwalton/SCS-CCT

4% improvement over Compact Transformers, which is considered SOTA

EDIT: As meragrin_ pointed out, I read the graph the wrong way. It's actually 4% worse. Sorry.

Re:Sharpened Cosine Distance as an Alternative for Convolutions by meragrin_ on Friday July 22, 2022 @02:08PM (#32195223)
Where do you see improvement? According to the graph and text, there is a 4% decrease in performance. It is slightly worse.