[Scummvm-cvs-logs] CVS: scummvm/doc 07_06.tex,NONE,1.1

[Torbjörn Andersson]

Update of /cvsroot/scummvm/scummvm/doc
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv12752

Added Files:
	07_06.tex 
Log Message:
Added missing part of my previous commit of patch #957544.


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\subsection{Output sample rate}



The output sample rate tells ScummVM how many sound samples to play per channel

per second. There is much that could be said on this subject, but most of it

would be irrelevant here. The short version is that for most games 22050 Hz is

fine, but in some cases 44100 Hz is preferable. On extremely low-end systems

you may want to use 11025 Hz, but it's unlikely that you have to worry about

that.



To elaborate, most of the sounds ScummVM has to play were sampled at either

22050 Hz or 11025 Hz. Using a higher sample rate will not magically improve the

quality of these sounds. Hence, 22050 Hz is fine.



Some games use CD audio. If you use compressed files for this, they are

probably sampled at 44100 Hz, so for these games that may be a better choice of

sample rate.



When using the Adlib, FM Towns, PC Speaker or IBM PCjr music drivers, ScummVM

is responsible for generating the samples. Usually 22050 Hz will be plenty for

these, but there is at least one piece of Adlib music in Beneath a Steeel Sky

that will sound a lot better at 44100 Hz.



Using frequencies in between is not recommended. For one thing, your sound card

may not support it. In theory, ScummVM should fall back on a sensible frequency

in that case, but don't count on it. More importantly, ScummVM has to resample

all sounds to its output frequency. This is much easier to do well if the

output frequency is a multiple of the original frequency.