godot/thirdparty/linuxbsd_headers/pulse/channelmap.h

#ifndef foochannelmaphfoo
#define foochannelmaphfoo

/***
  This file is part of PulseAudio.

  Copyright 2005-2006 Lennart Poettering
  Copyright 2006 Pierre Ossman <[email protected]> for Cendio AB

  PulseAudio 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 2.1 of the License,
  or (at your option) any later version.

  PulseAudio 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 PulseAudio; if not, see <http://www.gnu.org/licenses/>.
***/

#include <pulse/sample.h>
#include <pulse/cdecl.h>
#include <pulse/gccmacro.h>
#include <pulse/version.h>

/** \page channelmap Channel Maps
 *
 * \section overv_sec Overview
 *
 * Channel maps provide a way to associate channels in a stream with a
 * specific speaker position. This relieves applications of having to
 * make sure their channel order is identical to the final output.
 *
 * \section init_sec Initialisation
 *
 * A channel map consists of an array of \ref pa_channel_position values,
 * one for each channel. This array is stored together with a channel count
 * in a pa_channel_map structure.
 *
 * Before filling the structure, the application must initialise it using
 * pa_channel_map_init(). There are also a number of convenience functions
 * for standard channel mappings:
 *
 * \li pa_channel_map_init_mono() - Create a channel map with only mono audio.
 * \li pa_channel_map_init_stereo() - Create a standard stereo mapping.
 * \li pa_channel_map_init_auto() - Create a standard channel map for a specific number of channels
 * \li pa_channel_map_init_extend() - Similar to
 * pa_channel_map_init_auto() but synthesize a channel map if no
 * predefined one is known for the specified number of channels.
 *
 * \section conv_sec Convenience Functions
 *
 * The library contains a number of convenience functions for dealing with
 * channel maps:
 *
 * \li pa_channel_map_valid() - Tests if a channel map is valid.
 * \li pa_channel_map_equal() - Tests if two channel maps are identical.
 * \li pa_channel_map_snprint() - Creates a textual description of a channel
 *                                map.
 */

/** \file
 * Constants and routines for channel mapping handling
 *
 * See also \subpage channelmap
 */

PA_C_DECL_BEGIN

/** A list of channel labels */
pa_channel_position_t;

/** \cond fulldocs */
#define PA_CHANNEL_POSITION_INVALID
#define PA_CHANNEL_POSITION_MONO
#define PA_CHANNEL_POSITION_LEFT
#define PA_CHANNEL_POSITION_RIGHT
#define PA_CHANNEL_POSITION_CENTER
#define PA_CHANNEL_POSITION_FRONT_LEFT
#define PA_CHANNEL_POSITION_FRONT_RIGHT
#define PA_CHANNEL_POSITION_FRONT_CENTER
#define PA_CHANNEL_POSITION_REAR_CENTER
#define PA_CHANNEL_POSITION_REAR_LEFT
#define PA_CHANNEL_POSITION_REAR_RIGHT
#define PA_CHANNEL_POSITION_LFE
#define PA_CHANNEL_POSITION_SUBWOOFER
#define PA_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER
#define PA_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER
#define PA_CHANNEL_POSITION_SIDE_LEFT
#define PA_CHANNEL_POSITION_SIDE_RIGHT
#define PA_CHANNEL_POSITION_AUX0
#define PA_CHANNEL_POSITION_AUX1
#define PA_CHANNEL_POSITION_AUX2
#define PA_CHANNEL_POSITION_AUX3
#define PA_CHANNEL_POSITION_AUX4
#define PA_CHANNEL_POSITION_AUX5
#define PA_CHANNEL_POSITION_AUX6
#define PA_CHANNEL_POSITION_AUX7
#define PA_CHANNEL_POSITION_AUX8
#define PA_CHANNEL_POSITION_AUX9
#define PA_CHANNEL_POSITION_AUX10
#define PA_CHANNEL_POSITION_AUX11
#define PA_CHANNEL_POSITION_AUX12
#define PA_CHANNEL_POSITION_AUX13
#define PA_CHANNEL_POSITION_AUX14
#define PA_CHANNEL_POSITION_AUX15
#define PA_CHANNEL_POSITION_AUX16
#define PA_CHANNEL_POSITION_AUX17
#define PA_CHANNEL_POSITION_AUX18
#define PA_CHANNEL_POSITION_AUX19
#define PA_CHANNEL_POSITION_AUX20
#define PA_CHANNEL_POSITION_AUX21
#define PA_CHANNEL_POSITION_AUX22
#define PA_CHANNEL_POSITION_AUX23
#define PA_CHANNEL_POSITION_AUX24
#define PA_CHANNEL_POSITION_AUX25
#define PA_CHANNEL_POSITION_AUX26
#define PA_CHANNEL_POSITION_AUX27
#define PA_CHANNEL_POSITION_AUX28
#define PA_CHANNEL_POSITION_AUX29
#define PA_CHANNEL_POSITION_AUX30
#define PA_CHANNEL_POSITION_AUX31
#define PA_CHANNEL_POSITION_TOP_CENTER
#define PA_CHANNEL_POSITION_TOP_FRONT_LEFT
#define PA_CHANNEL_POSITION_TOP_FRONT_RIGHT
#define PA_CHANNEL_POSITION_TOP_FRONT_CENTER
#define PA_CHANNEL_POSITION_TOP_REAR_LEFT
#define PA_CHANNEL_POSITION_TOP_REAR_RIGHT
#define PA_CHANNEL_POSITION_TOP_REAR_CENTER
#define PA_CHANNEL_POSITION_MAX
/** \endcond */

/** A mask of channel positions. \since 0.9.16 */
pa_channel_position_mask_t;

/** Makes a bit mask from a channel position. \since 0.9.16 */
#define PA_CHANNEL_POSITION_MASK(f)

/** A list of channel mapping definitions for pa_channel_map_init_auto() */
pa_channel_map_def_t;

/** \cond fulldocs */
#define PA_CHANNEL_MAP_AIFF
#define PA_CHANNEL_MAP_ALSA
#define PA_CHANNEL_MAP_AUX
#define PA_CHANNEL_MAP_WAVEEX
#define PA_CHANNEL_MAP_OSS
#define PA_CHANNEL_MAP_DEF_MAX
#define PA_CHANNEL_MAP_DEFAULT
/** \endcond */

/** A channel map which can be used to attach labels to specific
 * channels of a stream. These values are relevant for conversion and
 * mixing of streams */
pa_channel_map;

/** Initialize the specified channel map and return a pointer to
 * it. The channel map will have a defined state but
 * pa_channel_map_valid() will fail for it. */
pa_channel_map* pa_channel_map_init(pa_channel_map *m);

/** Initialize the specified channel map for monaural audio and return a pointer to it */
pa_channel_map* pa_channel_map_init_mono(pa_channel_map *m);

/** Initialize the specified channel map for stereophonic audio and return a pointer to it */
pa_channel_map* pa_channel_map_init_stereo(pa_channel_map *m);

/** Initialize the specified channel map for the specified number of
 * channels using default labels and return a pointer to it. This call
 * will fail (return NULL) if there is no default channel map known for this
 * specific number of channels and mapping. */
pa_channel_map* pa_channel_map_init_auto(pa_channel_map *m, unsigned channels, pa_channel_map_def_t def);

/** Similar to pa_channel_map_init_auto() but instead of failing if no
 * default mapping is known with the specified parameters it will
 * synthesize a mapping based on a known mapping with fewer channels
 * and fill up the rest with AUX0...AUX31 channels  \since 0.9.11 */
pa_channel_map* pa_channel_map_init_extend(pa_channel_map *m, unsigned channels, pa_channel_map_def_t def);

/** Return a text label for the specified channel position */
const char* pa_channel_position_to_string(pa_channel_position_t pos) PA_GCC_PURE;

/** The inverse of pa_channel_position_to_string(). \since 0.9.16 */
pa_channel_position_t pa_channel_position_from_string(const char *s) PA_GCC_PURE;

/** Return a human readable text label for the specified channel position. \since 0.9.7 */
const char* pa_channel_position_to_pretty_string(pa_channel_position_t pos);

/** The maximum length of strings returned by
 * pa_channel_map_snprint(). Please note that this value can change
 * with any release without warning and without being considered API
 * or ABI breakage. You should not use this definition anywhere where
 * it might become part of an ABI. */
#define PA_CHANNEL_MAP_SNPRINT_MAX

/** Make a human readable string from the specified channel map */
char* pa_channel_map_snprint(char *s, size_t l, const pa_channel_map *map);

/** Parse a channel position list or well-known mapping name into a
 * channel map structure. This turns the output of
 * pa_channel_map_snprint() and pa_channel_map_to_name() back into a
 * pa_channel_map */
pa_channel_map *pa_channel_map_parse(pa_channel_map *map, const char *s);

/** Compare two channel maps. Return 1 if both match. */
int pa_channel_map_equal(const pa_channel_map *a, const pa_channel_map *b) PA_GCC_PURE;

/** Return non-zero if the specified channel map is considered valid */
int pa_channel_map_valid(const pa_channel_map *map) PA_GCC_PURE;

/** Return non-zero if the specified channel map is compatible with
 * the specified sample spec. \since 0.9.12 */
int pa_channel_map_compatible(const pa_channel_map *map, const pa_sample_spec *ss) PA_GCC_PURE;

/** Returns non-zero if every channel defined in b is also defined in a. \since 0.9.15 */
int pa_channel_map_superset(const pa_channel_map *a, const pa_channel_map *b) PA_GCC_PURE;

/** Returns non-zero if it makes sense to apply a volume 'balance'
 * with this mapping, i.e.\ if there are left/right channels
 * available. \since 0.9.15 */
int pa_channel_map_can_balance(const pa_channel_map *map) PA_GCC_PURE;

/** Returns non-zero if it makes sense to apply a volume 'fade'
 * (i.e.\ 'balance' between front and rear) with this mapping, i.e.\ if
 * there are front/rear channels available. \since 0.9.15 */
int pa_channel_map_can_fade(const pa_channel_map *map) PA_GCC_PURE;

/** Returns non-zero if it makes sense to apply a volume 'lfe balance'
 * (i.e.\ 'balance' between LFE and non-LFE channels) with this mapping,
 *  i.e.\ if there are LFE and non-LFE channels available. \since 8.0 */
int pa_channel_map_can_lfe_balance(const pa_channel_map *map) PA_GCC_PURE;

/** Tries to find a well-known channel mapping name for this channel
 * mapping, i.e.\ "stereo", "surround-71" and so on. If the channel
 * mapping is unknown NULL will be returned. This name can be parsed
 * with pa_channel_map_parse() \since 0.9.15 */
const char* pa_channel_map_to_name(const pa_channel_map *map) PA_GCC_PURE;

/** Tries to find a human readable text label for this channel
mapping, i.e.\ "Stereo", "Surround 7.1" and so on. If the channel
mapping is unknown NULL will be returned. \since 0.9.15 */
const char* pa_channel_map_to_pretty_name(const pa_channel_map *map) PA_GCC_PURE;

/** Returns non-zero if the specified channel position is available at
 * least once in the channel map. \since 0.9.16 */
int pa_channel_map_has_position(const pa_channel_map *map, pa_channel_position_t p) PA_GCC_PURE;

/** Generates a bit mask from a channel map. \since 0.9.16 */
pa_channel_position_mask_t pa_channel_map_mask(const pa_channel_map *map) PA_GCC_PURE;

PA_C_DECL_END

#endif