[5041] | 1 | .TH "roar_vs_volume_get" "3" "May 2011" "RoarAudio" "RoarAudio Programmer's Manual" |
---|
| 2 | |
---|
| 3 | .SH NAME |
---|
| 4 | roar_vs_volume_get, roar_vs_volume_mono, roar_vs_volume_stereo \- Get or set volume for audio stream |
---|
| 5 | |
---|
| 6 | .SH SYNOPSIS |
---|
| 7 | |
---|
| 8 | #include <roaraudio.h> |
---|
| 9 | |
---|
| 10 | int roar_vs_volume_get (roar_vs_t * vss, float * l, float * r, int * error); |
---|
| 11 | |
---|
| 12 | int roar_vs_volume_mono (roar_vs_t * vss, float c, int * error); |
---|
| 13 | |
---|
| 14 | int roar_vs_volume_stereo (roar_vs_t * vss, float l, float r, int * error); |
---|
| 15 | |
---|
| 16 | .SH "DESCRIPTION" |
---|
| 17 | Those functions are used to get or set volume for the given stream. |
---|
| 18 | |
---|
| 19 | \fBroar_vs_volume_get()\fR gets the volume for the given stream in stereo form as |
---|
| 20 | a left and a right component (L/R). If you need the mono volume just devide the sum of both |
---|
| 21 | by two. See examples below. |
---|
| 22 | |
---|
| 23 | \fBroar_vs_volume_mono()\fR sets the mono volume for the stream. Balance information is not kept. |
---|
| 24 | |
---|
| 25 | \fBroar_vs_volume_stereo()\fR sets the stereo volume for the stream as left and rigth component (L/R). |
---|
| 26 | |
---|
| 27 | .SH "PARAMETERS" |
---|
| 28 | .TP |
---|
| 29 | \fBvss\fR |
---|
| 30 | The VS object for wich volume is get or set. |
---|
| 31 | |
---|
| 32 | .TP |
---|
| 33 | \fBl\fR, \fBr\fR, \fBc\fR |
---|
| 34 | The volume for left, right or center (mono) channel. Value is a float in range zero to one. |
---|
| 35 | Zero means this channel is fully muted. One means the channel is passed without altering the amplitude. |
---|
| 36 | |
---|
| 37 | Small numerical errors are detected and corrected. Bigger errors will result in a out of range error. |
---|
| 38 | |
---|
| 39 | Note that to mute the stream you MUST NOT use volume setting but \fBroar_vs_mute\fR(3). |
---|
| 40 | |
---|
| 41 | .TP |
---|
| 42 | \fBerror\fR |
---|
| 43 | This is a pointer to a integer used to store the error value in case of error. |
---|
| 44 | This can be NULL if not used but it is very recommended to use this error value to report |
---|
| 45 | good error messages to the user. |
---|
| 46 | |
---|
| 47 | .SH "RETURN VALUE" |
---|
| 48 | On success these calls return 0. On error, \-1 is returned. |
---|
| 49 | |
---|
| 50 | .SH "EXAMPLES" |
---|
| 51 | Getting mono volume: |
---|
| 52 | |
---|
| 53 | float l, r, c; |
---|
| 54 | int err; |
---|
| 55 | |
---|
[5100] | 56 | if ( roar_vs_volume_get(vss, &l, &r, &err) == \-1 ) { |
---|
[5041] | 57 | /* handle error */ |
---|
| 58 | } |
---|
| 59 | c = (l + r)/2.; |
---|
| 60 | |
---|
| 61 | .SH "SEE ALSO" |
---|
| 62 | \fBroarvs\fR(7), |
---|
| 63 | \fBlibroar\fR(7), |
---|
| 64 | \fBRoarAudio\fR(7). |
---|
| 65 | |
---|
| 66 | .\" ll |
---|