pulseaudio/polyp/volume.h
Lennart Poettering e1f008f2a3 commit liboil porting changes
git-svn-id: file:///home/lennart/svn/public/pulseaudio/branches/liboil-test@344 fefdeb5f-60dc-0310-8127-8f9354f1896f
2005-09-15 23:42:56 +00:00

98 lines
3 KiB
C

#ifndef foovolumehfoo
#define foovolumehfoo
/* $Id$ */
/***
This file is part of polypaudio.
polypaudio is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.
polypaudio is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with polypaudio; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA.
***/
#include <inttypes.h>
#include <polyp/cdecl.h>
#include <polyp/sample.h>
/** \file
* Constants and routines for volume handling */
PA_C_DECL_BEGIN
/** Volume specification:
* PA_VOLUME_MUTED: silence;
* < PA_VOLUME_NORM: decreased volume;
* PA_VOLUME_NORM: normal volume;
* > PA_VOLUME_NORM: increased volume */
typedef uint32_t pa_volume_t;
/** Normal volume (100%) */
#define PA_VOLUME_NORM (0x10000)
/** Muted volume (0%) */
#define PA_VOLUME_MUTED (0)
/** A structure encapsulating a per-channel volume */
struct pa_cvolume {
uint8_t channels;
pa_volume_t values[PA_CHANNELS_MAX];
};
/** Return non-zero when *a == *b */
int pa_cvolume_equal(const struct pa_cvolume *a, const struct pa_cvolume *b);
/** Set the volume of all channels to PA_VOLUME_NORM */
void pa_cvolume_reset(struct pa_cvolume *a);
/** Set the volume of all channels to PA_VOLUME_MUTED */
void pa_cvolume_mute(struct pa_cvolume *a);
/** Set the volume of all channels to the specified parameter */
void pa_cvolume_set(struct pa_cvolume *a, pa_volume_t v);
/** Pretty print a volume structure */
char *pa_cvolume_snprintf(char *s, size_t l, const struct pa_cvolume *c, unsigned channels);
/** Return the average volume of all channels */
pa_volume_t pa_cvolume_avg(const struct pa_cvolume *a);
/** Return non-zero if the volume of all channels is equal to the specified value */
int pa_cvolume_channels_equal_to(const struct pa_cvolume *a, uint8_t channels, pa_volume_t v);
/** Multiply two volumes specifications, return the result. This uses PA_VOLUME_NORM as neutral element of multiplication. */
pa_volume_t pa_sw_volume_multiply(pa_volume_t a, pa_volume_t b);
/** Convert a decibel value to a volume. \since 0.4 */
pa_volume_t pa_sw_volume_from_dB(double f);
/** Convert a volume to a decibel value. \since 0.4 */
double pa_sw_volume_to_dB(pa_volume_t v);
/** Convert a linear factor to a volume. \since 0.8 */
pa_volume_t pa_sw_volume_from_linear(double v);
/** Convert a volume to a linear factor. \since 0.8 */
double pa_sw_volume_to_linear(pa_volume_t v);
#ifdef INFINITY
#define PA_DECIBEL_MININFTY (-INFINITY)
#else
/** This value is used as minus infinity when using pa_volume_{to,from}_dB(). \since 0.4 */
#define PA_DECIBEL_MININFTY (-200)
#endif
PA_C_DECL_END
#endif