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Subject: dB meter status quo and future
From: Andreas Zwirtes (zwirtes_at_gmx.de)
Date: 2002-10-07


Notes:

Paul Suade pointed out, that the division is very time consuming. I will
put a focus on that
in the next version, if this is of interest (just mail me). Although the
code looks very easy,
it's kind of hard work to get the values for all constants. It took me
nearly a day to
write the math software that helped me to aquire the values. Every
change in the
in/out parameter range will render the constants useless. So if we have
to do that, we
should do it once and keep the ranges fixed. I'll be on IRC for
discussion about that.
The main reason for that is the integer inclination (m). It causes the
error to rise very
quickly. This is somehow like solving a problem with three unknown
variables and only
one equation. Not mentioning some side-effects.

Phil: Thank you for putting the code in. The code is well tested an
keeps its output in
range (if the input value is in range). So the display should not fry
when using the
calc_dB function. If it does, inform me please.

Andreas aka radhard



Page was last modified "Jan 10 2012" The Rockbox Crew
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