Re: zero value with samples

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#385

From: Mark Jacobs
Date: Tue, 26 Oct 2004 09:08

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Thanks Tom. That formula certainly works on all PC systems I've ever tried it
on! Example apps using 8-bit unsigned samples are in VU meters at
http://www.jacobsm.com/index.htm#sft - look at MJ Player and MJ Calculator.
-- 
Mark Jacobs

"Tom|420" <tom420.duhamel@gmail.com> wrote in message
news:417db647$1@newsgroups.borland.com...
| Fraser Ross wrote:
|
| > "Mark Jacobs"
| >>This is what I use for 8-bit samples :-
| >>int lv=(int)((unsigned char)wvhdr->lpData[0])-128;
| >
| > That isn't an answer to my question.  BTW I don't think the cast to int is
| > necessary.
| > My former suggestion of 128 positive values and 128 negative values and
| > using 0 as if it is the midpoint seems to be the norm.
|
| Mark Jacobs answer is the only good answer to your question. If you
| don't trust that answer do some research (although you will probably
| find that audio experts don't publish much free stuff on the net -- 
| actualy they don't even publish much for-a-fee stuff anywhere).

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Subject: Re: zero value with samples
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