Constants and routines for channel mapping handling. More...
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Constants and routines for channel mapping handling.
See also Channel Maps
| #define PA_CHANNEL_MAP_SNPRINT_MAX 336 |
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_POSITION_MASK | ( | f ) | ((pa_channel_position_mask_t) (1ULL << (f))) |
Makes a bit mask from a channel position.
| typedef struct pa_channel_map pa_channel_map |
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 enum pa_channel_map_def pa_channel_map_def_t |
A list of channel mapping definitions for pa_channel_map_init_auto()
| typedef uint64_t pa_channel_position_mask_t |
A mask of channel positions.
| typedef enum pa_channel_position pa_channel_position_t |
A list of channel labels.
| enum pa_channel_map_def |
A list of channel mapping definitions for pa_channel_map_init_auto()
| enum pa_channel_position |
A list of channel labels.
| int pa_channel_map_can_balance | ( | const pa_channel_map * | map ) |
Returns non-zero if it makes sense to apply a volume 'balance' with this mapping, i.e.
if there are left/right channels available.
| int pa_channel_map_can_fade | ( | const pa_channel_map * | map ) |
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.
| int pa_channel_map_compatible | ( | const pa_channel_map * | map, |
| const pa_sample_spec * | ss | ||
| ) |
Return non-zero if the specified channel map is compatible with the specified sample spec.
| int pa_channel_map_equal | ( | const pa_channel_map * | a, |
| const pa_channel_map * | b | ||
| ) |
Compare two channel maps.
Return 1 if both match.
| int pa_channel_map_has_position | ( | const pa_channel_map * | map, |
| pa_channel_position_t | p | ||
| ) |
Returns TRUE if the specified channel position is available at least once in the channel map.
| pa_channel_map* pa_channel_map_init | ( | pa_channel_map * | m ) |
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_auto | ( | pa_channel_map * | m, |
| unsigned | channels, | ||
| pa_channel_map_def_t | def | ||
| ) |
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_extend | ( | 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.
| pa_channel_map* pa_channel_map_init_mono | ( | 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_stereo | ( | pa_channel_map * | m ) |
Initialize the specified channel map for stereophonic audio and return a pointer to it.
| pa_channel_position_mask_t pa_channel_map_mask | ( | const pa_channel_map * | map ) |
Generates a bit mask from a channel map.
| pa_channel_map* pa_channel_map_parse | ( | pa_channel_map * | map, |
| const char * | s | ||
| ) |
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
| char* pa_channel_map_snprint | ( | char * | s, |
| size_t | l, | ||
| const pa_channel_map * | map | ||
| ) |
Make a human readable string from the specified channel map.
| int pa_channel_map_superset | ( | const pa_channel_map * | a, |
| const pa_channel_map * | b | ||
| ) |
Returns non-zero if every channel defined in b is also defined in a.
| const char* pa_channel_map_to_name | ( | const pa_channel_map * | map ) |
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()
| const char* pa_channel_map_to_pretty_name | ( | const pa_channel_map * | map ) |
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.
| int pa_channel_map_valid | ( | const pa_channel_map * | map ) |
Return non-zero if the specified channel map is considered valid.
| pa_channel_position_t pa_channel_position_from_string | ( | const char * | s ) |
The inverse of pa_channel_position_to_string().
| const char* pa_channel_position_to_pretty_string | ( | pa_channel_position_t | pos ) |
Return a human readable text label for the specified channel position.
| const char* pa_channel_position_to_string | ( | pa_channel_position_t | pos ) |
Return a text label for the specified channel position.
1.7.2