Provided by:
libroar-dev_0.4-2_i386 
NAME
roar_vs_volume_get, roar_vs_volume_mono, roar_vs_volume_stereo - Get or
set volume for audio stream
SYNOPSIS
#include <roaraudio.h>
int roar_vs_volume_get (roar_vs_t * vss, float * l, float * r,
int * error);
int roar_vs_volume_mono (roar_vs_t * vss, float c, int * error);
int roar_vs_volume_stereo (roar_vs_t * vss, float l, float r, int *
error);
DESCRIPTION
Those functions are used to get or set volume for the given stream.
roar_vs_volume_get() gets the volume for the given stream in stereo
form as a left and a right component (L/R). If you need the mono volume
just devide the sum of both by two. See examples below.
roar_vs_volume_mono() sets the mono volume for the stream. Balance
information is not kept.
roar_vs_volume_stereo() sets the stereo volume for the stream as left
and rigth component (L/R).
PARAMETERS
vss The VS object for wich volume is get or set.
l, r, c
The volume for left, right or center (mono) channel. Value is a
float in range zero to one. Zero means this channel is fully
muted. One means the channel is passed without altering the
amplitude.
Small numerical errors are detected and corrected. Bigger errors
will result in a out of range error.
Note that to mute the stream you MUST NOT use volume setting but
roar_vs_mute(3).
error This is a pointer to a integer used to store the error value in
case of error. This can be NULL if not used but it is very
recommended to use this error value to report good error
messages to the user.
RETURN VALUE
On success these calls return 0. On error, -1 is returned.
EXAMPLES
Getting mono volume:
float l, r, c;
int err;
if ( roar_vs_volume_get(vss, &l, &r, &err) == -1 ) {
/* handle error */
}
c = (l + r)/2.;
SEE ALSO
roarvs(7), libroar(7), RoarAudio(7).