[HW] - KOMPRESE ZVUKU

[Peter Rosko]

Zdravim, Alaw a ulaw su dost podobne logaritmickemu priebehu, Analog
Devices vyraba operacne zosilnovace s takymto priebehom, potom staci
normalny ad resp da prevodnik...
peto rosko

On Mon, 23 Aug 1999, PaPouch wrote:

> Nelinearni komprese se bezne pouziva pro dig. prenos zvuku. Jsou na to dva
> standardy - u(mikro)-law (americky) a A-law (evropsky). 16 bitu se
> komprimuje do 8 a po expanzi je mozne ziskat  signal odpovidajici kvlaitou
> 14 bitovemu
> kodovani.
> 
> Pavel Poucha
> 
> 
> -----Původní zpráva-----
> Od: Snail Instruments <snail@iol.cz>
> Komu: Multiple recipients of list <hw-news@list.gin.cz>
> Datum: 22. srpna 1999 10:26
> Předmět: Re: [HW] - KOMPRESE ZVUKU
> 
> 
> >Jeste ke kompresi zvuku - v konferenci Chipdir se objevil nasledujici
> >zajimavy prispevek, urcite stoji za to, vzit uvedene skutecnosti v uvahu.
> >
> >>What seems to be important when you work with speech is the fact that =
> >>speech
> >>is made of low intensity sound that should be precisely rendered and =
> >>high
> >>intensity "spikes" (I mean with infrequent rises ) that should be =
> >>rendered
> >>too.=20
> >>Of course, if you sample at 16 or 24 bit you can get a perfect sound =
> >>quality
> >>respective to what we discussed. The trick is to use a non-linear =
> >>analog-to
> >>digital converter to digitize the speech. The difference in input =
> >>change
> >>that makes the digital output change is smaller if the amplitude is low =
> >>than
> >>when it is high.
> >
> >J. Hanzal
> >
> >
> >======================================================================
> >Electronical devices for chemical laboratory, custom electonics design
> >----------------------------------------------------------------------
> >Snail Instruments                     Josef Hanzal, M. S.
> >Vojanova 615                          phone/fax: +420-311-24433
> >266 01 Beroun                         e-mail: snail@iol.cz
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> >
> >
> 
>