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From: "Steve Simon" <steve@quintile.net>
Date: Mon, 15 Feb 2021 10:55:09 +0000
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X-Bullshit: patented software ACPI over WEB2.0 plugin configuration layer 
Subject: Re: [9front] games/snes audio patches
Reply-To: 9front@9front.org
Precedence: bulk

Re: cheap audio upsampling

nearest neighbour is a crude upconverter, linear is much better,
a halfband filter with a few taps (maybe 8) should be good enough IMHO,
though I am not a game player so you may disagree. You can improve the
resolts of a short halfband filter by feeding it your linerly interpolated
stream.

Don't be tempted to filter only the missing samples as you are likely
to have gain or/and phase ripples due to the rounding errors of your
coeficents. itsbetter to filter everything equally well/badly.

-Steve