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Diffstat (limited to 'src/pulse/channelmap.h')
| -rw-r--r-- | src/pulse/channelmap.h | 368 |
1 files changed, 368 insertions, 0 deletions
diff --git a/src/pulse/channelmap.h b/src/pulse/channelmap.h new file mode 100644 index 0000000..290e1ed --- /dev/null +++ b/src/pulse/channelmap.h @@ -0,0 +1,368 @@ +#ifndef foochannelmaphfoo +#define foochannelmaphfoo + +/*** + This file is part of PulseAudio. + + Copyright 2005-2006 Lennart Poettering + Copyright 2006 Pierre Ossman <ossman@cendio.se> 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 */ +typedef enum pa_channel_position { + PA_CHANNEL_POSITION_INVALID = -1, + PA_CHANNEL_POSITION_MONO = 0, + + PA_CHANNEL_POSITION_FRONT_LEFT, /**< Apple, Dolby call this 'Left' */ + PA_CHANNEL_POSITION_FRONT_RIGHT, /**< Apple, Dolby call this 'Right' */ + PA_CHANNEL_POSITION_FRONT_CENTER, /**< Apple, Dolby call this 'Center' */ + +/** \cond fulldocs */ + PA_CHANNEL_POSITION_LEFT = PA_CHANNEL_POSITION_FRONT_LEFT, + PA_CHANNEL_POSITION_RIGHT = PA_CHANNEL_POSITION_FRONT_RIGHT, + PA_CHANNEL_POSITION_CENTER = PA_CHANNEL_POSITION_FRONT_CENTER, +/** \endcond */ + + PA_CHANNEL_POSITION_REAR_CENTER, /**< Microsoft calls this 'Back Center', Apple calls this 'Center Surround', Dolby calls this 'Surround Rear Center' */ + PA_CHANNEL_POSITION_REAR_LEFT, /**< Microsoft calls this 'Back Left', Apple calls this 'Left Surround' (!), Dolby calls this 'Surround Rear Left' */ + PA_CHANNEL_POSITION_REAR_RIGHT, /**< Microsoft calls this 'Back Right', Apple calls this 'Right Surround' (!), Dolby calls this 'Surround Rear Right' */ + + PA_CHANNEL_POSITION_LFE, /**< Microsoft calls this 'Low Frequency', Apple calls this 'LFEScreen' */ +/** \cond fulldocs */ + PA_CHANNEL_POSITION_SUBWOOFER = PA_CHANNEL_POSITION_LFE, +/** \endcond */ + + PA_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER, /**< Apple, Dolby call this 'Left Center' */ + PA_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER, /**< Apple, Dolby call this 'Right Center */ + + PA_CHANNEL_POSITION_SIDE_LEFT, /**< Apple calls this 'Left Surround Direct', Dolby calls this 'Surround Left' (!) */ + PA_CHANNEL_POSITION_SIDE_RIGHT, /**< Apple calls this 'Right Surround Direct', Dolby calls this 'Surround Right' (!) */ + + PA_CHANNEL_POSITION_AUX0, + PA_CHANNEL_POSITION_AUX1, + PA_CHANNEL_POSITION_AUX2, + PA_CHANNEL_POSITION_AUX3, + PA_CHANNEL_POSITION_AUX4, + PA_CHANNEL_POSITION_AUX5, + PA_CHANNEL_POSITION_AUX6, + PA_CHANNEL_POSITION_AUX7, + PA_CHANNEL_POSITION_AUX8, + PA_CHANNEL_POSITION_AUX9, + PA_CHANNEL_POSITION_AUX10, + PA_CHANNEL_POSITION_AUX11, + PA_CHANNEL_POSITION_AUX12, + PA_CHANNEL_POSITION_AUX13, + PA_CHANNEL_POSITION_AUX14, + PA_CHANNEL_POSITION_AUX15, + PA_CHANNEL_POSITION_AUX16, + PA_CHANNEL_POSITION_AUX17, + PA_CHANNEL_POSITION_AUX18, + PA_CHANNEL_POSITION_AUX19, + PA_CHANNEL_POSITION_AUX20, + PA_CHANNEL_POSITION_AUX21, + PA_CHANNEL_POSITION_AUX22, + PA_CHANNEL_POSITION_AUX23, + PA_CHANNEL_POSITION_AUX24, + PA_CHANNEL_POSITION_AUX25, + PA_CHANNEL_POSITION_AUX26, + PA_CHANNEL_POSITION_AUX27, + PA_CHANNEL_POSITION_AUX28, + PA_CHANNEL_POSITION_AUX29, + PA_CHANNEL_POSITION_AUX30, + PA_CHANNEL_POSITION_AUX31, + + PA_CHANNEL_POSITION_TOP_CENTER, /**< Apple calls this 'Top Center Surround' */ + + PA_CHANNEL_POSITION_TOP_FRONT_LEFT, /**< Apple calls this 'Vertical Height Left' */ + PA_CHANNEL_POSITION_TOP_FRONT_RIGHT, /**< Apple calls this 'Vertical Height Right' */ + PA_CHANNEL_POSITION_TOP_FRONT_CENTER, /**< Apple calls this 'Vertical Height Center' */ + + PA_CHANNEL_POSITION_TOP_REAR_LEFT, /**< Microsoft and Apple call this 'Top Back Left' */ + PA_CHANNEL_POSITION_TOP_REAR_RIGHT, /**< Microsoft and Apple call this 'Top Back Right' */ + PA_CHANNEL_POSITION_TOP_REAR_CENTER, /**< Microsoft and Apple call this 'Top Back Center' */ + + PA_CHANNEL_POSITION_MAX +} pa_channel_position_t; + +/** \cond fulldocs */ +#define PA_CHANNEL_POSITION_INVALID PA_CHANNEL_POSITION_INVALID +#define PA_CHANNEL_POSITION_MONO PA_CHANNEL_POSITION_MONO +#define PA_CHANNEL_POSITION_LEFT PA_CHANNEL_POSITION_LEFT +#define PA_CHANNEL_POSITION_RIGHT PA_CHANNEL_POSITION_RIGHT +#define PA_CHANNEL_POSITION_CENTER PA_CHANNEL_POSITION_CENTER +#define PA_CHANNEL_POSITION_FRONT_LEFT PA_CHANNEL_POSITION_FRONT_LEFT +#define PA_CHANNEL_POSITION_FRONT_RIGHT PA_CHANNEL_POSITION_FRONT_RIGHT +#define PA_CHANNEL_POSITION_FRONT_CENTER PA_CHANNEL_POSITION_FRONT_CENTER +#define PA_CHANNEL_POSITION_REAR_CENTER PA_CHANNEL_POSITION_REAR_CENTER +#define PA_CHANNEL_POSITION_REAR_LEFT PA_CHANNEL_POSITION_REAR_LEFT +#define PA_CHANNEL_POSITION_REAR_RIGHT PA_CHANNEL_POSITION_REAR_RIGHT +#define PA_CHANNEL_POSITION_LFE PA_CHANNEL_POSITION_LFE +#define PA_CHANNEL_POSITION_SUBWOOFER PA_CHANNEL_POSITION_SUBWOOFER +#define PA_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER PA_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER +#define PA_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER PA_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER +#define PA_CHANNEL_POSITION_SIDE_LEFT PA_CHANNEL_POSITION_SIDE_LEFT +#define PA_CHANNEL_POSITION_SIDE_RIGHT PA_CHANNEL_POSITION_SIDE_RIGHT +#define PA_CHANNEL_POSITION_AUX0 PA_CHANNEL_POSITION_AUX0 +#define PA_CHANNEL_POSITION_AUX1 PA_CHANNEL_POSITION_AUX1 +#define PA_CHANNEL_POSITION_AUX2 PA_CHANNEL_POSITION_AUX2 +#define PA_CHANNEL_POSITION_AUX3 PA_CHANNEL_POSITION_AUX3 +#define PA_CHANNEL_POSITION_AUX4 PA_CHANNEL_POSITION_AUX4 +#define PA_CHANNEL_POSITION_AUX5 PA_CHANNEL_POSITION_AUX5 +#define PA_CHANNEL_POSITION_AUX6 PA_CHANNEL_POSITION_AUX6 +#define PA_CHANNEL_POSITION_AUX7 PA_CHANNEL_POSITION_AUX7 +#define PA_CHANNEL_POSITION_AUX8 PA_CHANNEL_POSITION_AUX8 +#define PA_CHANNEL_POSITION_AUX9 PA_CHANNEL_POSITION_AUX9 +#define PA_CHANNEL_POSITION_AUX10 PA_CHANNEL_POSITION_AUX10 +#define PA_CHANNEL_POSITION_AUX11 PA_CHANNEL_POSITION_AUX11 +#define PA_CHANNEL_POSITION_AUX12 PA_CHANNEL_POSITION_AUX12 +#define PA_CHANNEL_POSITION_AUX13 PA_CHANNEL_POSITION_AUX13 +#define PA_CHANNEL_POSITION_AUX14 PA_CHANNEL_POSITION_AUX14 +#define PA_CHANNEL_POSITION_AUX15 PA_CHANNEL_POSITION_AUX15 +#define PA_CHANNEL_POSITION_AUX16 PA_CHANNEL_POSITION_AUX16 +#define PA_CHANNEL_POSITION_AUX17 PA_CHANNEL_POSITION_AUX17 +#define PA_CHANNEL_POSITION_AUX18 PA_CHANNEL_POSITION_AUX18 +#define PA_CHANNEL_POSITION_AUX19 PA_CHANNEL_POSITION_AUX19 +#define PA_CHANNEL_POSITION_AUX20 PA_CHANNEL_POSITION_AUX20 +#define PA_CHANNEL_POSITION_AUX21 PA_CHANNEL_POSITION_AUX21 +#define PA_CHANNEL_POSITION_AUX22 PA_CHANNEL_POSITION_AUX22 +#define PA_CHANNEL_POSITION_AUX23 PA_CHANNEL_POSITION_AUX23 +#define PA_CHANNEL_POSITION_AUX24 PA_CHANNEL_POSITION_AUX24 +#define PA_CHANNEL_POSITION_AUX25 PA_CHANNEL_POSITION_AUX25 +#define PA_CHANNEL_POSITION_AUX26 PA_CHANNEL_POSITION_AUX26 +#define PA_CHANNEL_POSITION_AUX27 PA_CHANNEL_POSITION_AUX27 +#define PA_CHANNEL_POSITION_AUX28 PA_CHANNEL_POSITION_AUX28 +#define PA_CHANNEL_POSITION_AUX29 PA_CHANNEL_POSITION_AUX29 +#define PA_CHANNEL_POSITION_AUX30 PA_CHANNEL_POSITION_AUX30 +#define PA_CHANNEL_POSITION_AUX31 PA_CHANNEL_POSITION_AUX31 +#define PA_CHANNEL_POSITION_TOP_CENTER PA_CHANNEL_POSITION_TOP_CENTER +#define PA_CHANNEL_POSITION_TOP_FRONT_LEFT PA_CHANNEL_POSITION_TOP_FRONT_LEFT +#define PA_CHANNEL_POSITION_TOP_FRONT_RIGHT PA_CHANNEL_POSITION_TOP_FRONT_RIGHT +#define PA_CHANNEL_POSITION_TOP_FRONT_CENTER PA_CHANNEL_POSITION_TOP_FRONT_CENTER +#define PA_CHANNEL_POSITION_TOP_REAR_LEFT PA_CHANNEL_POSITION_TOP_REAR_LEFT +#define PA_CHANNEL_POSITION_TOP_REAR_RIGHT PA_CHANNEL_POSITION_TOP_REAR_RIGHT +#define PA_CHANNEL_POSITION_TOP_REAR_CENTER PA_CHANNEL_POSITION_TOP_REAR_CENTER +#define PA_CHANNEL_POSITION_MAX PA_CHANNEL_POSITION_MAX +/** \endcond */ + +/** A mask of channel positions. \since 0.9.16 */ +typedef uint64_t pa_channel_position_mask_t; + +/** Makes a bit mask from a channel position. \since 0.9.16 */ +#define PA_CHANNEL_POSITION_MASK(f) ((pa_channel_position_mask_t) (1ULL << (f))) + +/** A list of channel mapping definitions for pa_channel_map_init_auto() */ +typedef enum pa_channel_map_def { + PA_CHANNEL_MAP_AIFF, + /**< The mapping from RFC3551, which is based on AIFF-C */ + +/** \cond fulldocs */ + PA_CHANNEL_MAP_ALSA, + /**< The default mapping used by ALSA. This mapping is probably + * not too useful since ALSA's default channel mapping depends on + * the device string used. */ +/** \endcond */ + + PA_CHANNEL_MAP_AUX, + /**< Only aux channels */ + + PA_CHANNEL_MAP_WAVEEX, + /**< Microsoft's WAVEFORMATEXTENSIBLE mapping. This mapping works + * as if all LSBs of dwChannelMask are set. */ + +/** \cond fulldocs */ + PA_CHANNEL_MAP_OSS, + /**< The default channel mapping used by OSS as defined in the OSS + * 4.0 API specs. This mapping is probably not too useful since + * the OSS API has changed in this respect and no longer knows a + * default channel mapping based on the number of channels. */ +/** \endcond */ + + /**< Upper limit of valid channel mapping definitions */ + PA_CHANNEL_MAP_DEF_MAX, + + PA_CHANNEL_MAP_DEFAULT = PA_CHANNEL_MAP_AIFF + /**< The default channel map */ +} pa_channel_map_def_t; + +/** \cond fulldocs */ +#define PA_CHANNEL_MAP_AIFF PA_CHANNEL_MAP_AIFF +#define PA_CHANNEL_MAP_ALSA PA_CHANNEL_MAP_ALSA +#define PA_CHANNEL_MAP_AUX PA_CHANNEL_MAP_AUX +#define PA_CHANNEL_MAP_WAVEEX PA_CHANNEL_MAP_WAVEEX +#define PA_CHANNEL_MAP_OSS PA_CHANNEL_MAP_OSS +#define PA_CHANNEL_MAP_DEF_MAX PA_CHANNEL_MAP_DEF_MAX +#define PA_CHANNEL_MAP_DEFAULT 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 */ +typedef struct pa_channel_map { + uint8_t channels; + /**< Number of channels mapped */ + + pa_channel_position_t map[PA_CHANNELS_MAX]; + /**< Channel labels */ +} 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 336 + +/** Make a human readable string from the specified channel map. Returns \a s. */ +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 |