Constants and routines for volume handling. More...

Data Structures
struct	pa_cvolume
	A structure encapsulating a per-channel volume. More...

Macros
#define	PA_VOLUME_NORM ((pa_volume_t) 0x10000U)
	Normal volume (100%, 0 dB) More...

#define	PA_VOLUME_MUTED ((pa_volume_t) 0U)
	Muted (minimal valid) volume (0%, -inf dB) More...

#define	PA_VOLUME_MAX ((pa_volume_t) UINT32_MAX/2)
	Maximum valid volume we can store. More...

#define	PA_VOLUME_UI_MAX (pa_sw_volume_from_dB(+11.0))
	Recommended maximum volume to show in user facing UIs. More...

#define	PA_VOLUME_INVALID ((pa_volume_t) UINT32_MAX)
	Special 'invalid' volume. More...

#define	PA_VOLUME_IS_VALID(v) ((v) <= PA_VOLUME_MAX)
	Check if volume is valid. More...

#define	PA_CLAMP_VOLUME(v) (PA_CLAMP_UNLIKELY((v), PA_VOLUME_MUTED, PA_VOLUME_MAX))
	Clamp volume to the permitted range. More...

#define	pa_cvolume_reset(a, n) pa_cvolume_set((a), (n), PA_VOLUME_NORM)
	Set the volume of the first n channels to PA_VOLUME_NORM. More...

#define	pa_cvolume_mute(a, n) pa_cvolume_set((a), (n), PA_VOLUME_MUTED)
	Set the volume of the first n channels to PA_VOLUME_MUTED. More...

#define	PA_CVOLUME_SNPRINT_MAX 320
	Maximum length of the strings returned by pa_cvolume_snprint(). More...

#define	PA_SW_CVOLUME_SNPRINT_DB_MAX 448
	Maximum length of the strings returned by pa_sw_cvolume_snprint_dB(). More...

#define	PA_CVOLUME_SNPRINT_VERBOSE_MAX 1984
	Maximum length of the strings returned by pa_cvolume_snprint_verbose(). More...

#define	PA_VOLUME_SNPRINT_MAX 10
	Maximum length of the strings returned by pa_volume_snprint(). More...

#define	PA_SW_VOLUME_SNPRINT_DB_MAX 11
	Maximum length of the strings returned by pa_sw_volume_snprint_dB(). More...

#define	PA_VOLUME_SNPRINT_VERBOSE_MAX 35
	Maximum length of the strings returned by pa_volume_snprint_verbose(). More...

#define	pa_cvolume_is_muted(a) pa_cvolume_channels_equal_to((a), PA_VOLUME_MUTED)
	Return 1 if the specified volume has all channels muted. More...

#define	pa_cvolume_is_norm(a) pa_cvolume_channels_equal_to((a), PA_VOLUME_NORM)
	Return 1 if the specified volume has all channels on normal level. More...

#define	PA_DECIBEL_MININFTY ((double) -200.0)
	This floor value is used as minus infinity when using pa_sw_volume_to_dB() / pa_sw_volume_from_dB(). More...

Typedefs
typedef uint32_t	pa_volume_t
	Volume specification: PA_VOLUME_MUTED: silence; < PA_VOLUME_NORM: decreased volume; PA_VOLUME_NORM: normal volume; PA_VOLUME_NORM: increased volume More...

typedef struct pa_cvolume	pa_cvolume
	A structure encapsulating a per-channel volume. More...

Functions
int	pa_cvolume_equal (const pa_cvolume a, const pa_cvolume b) PA_GCC_PURE
	Return non-zero when a == b, checking that both a and b have the same number of channels and that the volumes of channels in a equal those in b. More...

pa_cvolume *	pa_cvolume_init (pa_cvolume *a)
	Initialize the specified volume and return a pointer to it. More...

pa_cvolume *	pa_cvolume_set (pa_cvolume *a, unsigned channels, pa_volume_t v)
	Set the volume of the specified number of channels to the volume v. More...

char *	pa_cvolume_snprint (char s, size_t l, const pa_cvolume c)
	Pretty print a volume structure. More...

char *	pa_sw_cvolume_snprint_dB (char s, size_t l, const pa_cvolume c)
	Pretty print a volume structure, showing dB values. More...

char *	pa_cvolume_snprint_verbose (char s, size_t l, const pa_cvolume c, const pa_channel_map *map, int print_dB)
	Pretty print a volume structure in a verbose way. More...

char *	pa_volume_snprint (char *s, size_t l, pa_volume_t v)
	Pretty print a volume. More...

char *	pa_sw_volume_snprint_dB (char *s, size_t l, pa_volume_t v)
	Pretty print a volume but show dB values. More...

char *	pa_volume_snprint_verbose (char *s, size_t l, pa_volume_t v, int print_dB)
	Pretty print a volume in a verbose way. More...

pa_volume_t	pa_cvolume_avg (const pa_cvolume *a) PA_GCC_PURE
	Return the average volume of all channels. More...

pa_volume_t	pa_cvolume_avg_mask (const pa_cvolume a, const pa_channel_map cm, pa_channel_position_mask_t mask) PA_GCC_PURE
	Return the average volume of all channels that are included in the specified channel map with the specified channel position mask. More...

pa_volume_t	pa_cvolume_max (const pa_cvolume *a) PA_GCC_PURE
	Return the maximum volume of all channels. More...

pa_volume_t	pa_cvolume_max_mask (const pa_cvolume a, const pa_channel_map cm, pa_channel_position_mask_t mask) PA_GCC_PURE
	Return the maximum volume of all channels that are included in the specified channel map with the specified channel position mask. More...

pa_volume_t	pa_cvolume_min (const pa_cvolume *a) PA_GCC_PURE
	Return the minimum volume of all channels. More...

pa_volume_t	pa_cvolume_min_mask (const pa_cvolume a, const pa_channel_map cm, pa_channel_position_mask_t mask) PA_GCC_PURE
	Return the minimum volume of all channels that are included in the specified channel map with the specified channel position mask. More...

int	pa_cvolume_valid (const pa_cvolume *v) PA_GCC_PURE
	Return non-zero when the passed cvolume structure is valid. More...

int	pa_cvolume_channels_equal_to (const pa_cvolume *a, pa_volume_t v) PA_GCC_PURE
	Return non-zero if the volume of all channels is equal to the specified value. More...

pa_volume_t	pa_sw_volume_multiply (pa_volume_t a, pa_volume_t b) PA_GCC_CONST
	Multiply two volume specifications, return the result. More...

pa_cvolume *	pa_sw_cvolume_multiply (pa_cvolume dest, const pa_cvolume a, const pa_cvolume *b)
	Multiply two per-channel volumes and return the result in *dest. More...

pa_cvolume *	pa_sw_cvolume_multiply_scalar (pa_cvolume dest, const pa_cvolume a, pa_volume_t b)
	Multiply a per-channel volume with a scalar volume and return the result in *dest. More...

pa_volume_t	pa_sw_volume_divide (pa_volume_t a, pa_volume_t b) PA_GCC_CONST
	Divide two volume specifications, return the result. More...

pa_cvolume *	pa_sw_cvolume_divide (pa_cvolume dest, const pa_cvolume a, const pa_cvolume *b)
	Divide two per-channel volumes and return the result in *dest. More...

pa_cvolume *	pa_sw_cvolume_divide_scalar (pa_cvolume dest, const pa_cvolume a, pa_volume_t b)
	Divide a per-channel volume by a scalar volume and return the result in *dest. More...

pa_volume_t	pa_sw_volume_from_dB (double f) PA_GCC_CONST
	Convert a decibel value to a volume (amplitude, not power). More...

double	pa_sw_volume_to_dB (pa_volume_t v) PA_GCC_CONST
	Convert a volume to a decibel value (amplitude, not power). More...

pa_volume_t	pa_sw_volume_from_linear (double v) PA_GCC_CONST
	Convert a linear factor to a volume. More...

double	pa_sw_volume_to_linear (pa_volume_t v) PA_GCC_CONST
	Convert a volume to a linear factor. More...

pa_cvolume *	pa_cvolume_remap (pa_cvolume v, const pa_channel_map from, const pa_channel_map *to)
	Remap a volume from one channel mapping to a different channel mapping. More...

int	pa_cvolume_compatible (const pa_cvolume v, const pa_sample_spec ss) PA_GCC_PURE
	Return non-zero if the specified volume is compatible with the specified sample spec. More...

int	pa_cvolume_compatible_with_channel_map (const pa_cvolume v, const pa_channel_map cm) PA_GCC_PURE
	Return non-zero if the specified volume is compatible with the specified sample spec. More...

float	pa_cvolume_get_balance (const pa_cvolume v, const pa_channel_map map) PA_GCC_PURE
	Calculate a 'balance' value for the specified volume with the specified channel map. More...

pa_cvolume *	pa_cvolume_set_balance (pa_cvolume v, const pa_channel_map map, float new_balance)
	Adjust the 'balance' value for the specified volume with the specified channel map. More...

float	pa_cvolume_get_fade (const pa_cvolume v, const pa_channel_map map) PA_GCC_PURE
	Calculate a 'fade' value (i.e. 'balance' between front and rear) for the specified volume with the specified channel map. More...

pa_cvolume *	pa_cvolume_set_fade (pa_cvolume v, const pa_channel_map map, float new_fade)
	Adjust the 'fade' value (i.e. 'balance' between front and rear) for the specified volume with the specified channel map. More...

float	pa_cvolume_get_lfe_balance (const pa_cvolume v, const pa_channel_map map) PA_GCC_PURE
	Calculate a 'lfe balance' value for the specified volume with the specified channel map. More...

pa_cvolume *	pa_cvolume_set_lfe_balance (pa_cvolume v, const pa_channel_map map, float new_balance)
	Adjust the 'lfe balance' value for the specified volume with the specified channel map. More...

pa_cvolume *	pa_cvolume_scale (pa_cvolume *v, pa_volume_t max)
	Scale the passed pa_cvolume structure so that the maximum volume of all channels equals max. More...

pa_cvolume *	pa_cvolume_scale_mask (pa_cvolume v, pa_volume_t max, const pa_channel_map cm, pa_channel_position_mask_t mask)
	Scale the passed pa_cvolume structure so that the maximum volume of all channels selected via cm/mask equals max. More...

pa_cvolume *	pa_cvolume_set_position (pa_cvolume cv, const pa_channel_map map, pa_channel_position_t t, pa_volume_t v)
	Set the passed volume to all channels at the specified channel position. More...

pa_volume_t	pa_cvolume_get_position (const pa_cvolume cv, const pa_channel_map map, pa_channel_position_t t) PA_GCC_PURE
	Get the maximum volume of all channels at the specified channel position. More...

pa_cvolume *	pa_cvolume_merge (pa_cvolume dest, const pa_cvolume a, const pa_cvolume *b)
	This goes through all channels in a and b and sets the corresponding channel in dest to the greater volume of both. More...

pa_cvolume *	pa_cvolume_inc_clamp (pa_cvolume *v, pa_volume_t inc, pa_volume_t limit)
	Increase the volume passed in by 'inc', but not exceeding 'limit'. More...

pa_cvolume *	pa_cvolume_inc (pa_cvolume *v, pa_volume_t inc)
	Increase the volume passed in by 'inc'. More...

pa_cvolume *	pa_cvolume_dec (pa_cvolume *v, pa_volume_t dec)
	Decrease the volume passed in by 'dec'. More...

Detailed Description

Constants and routines for volume handling.

Macro Definition Documentation

◆ PA_CLAMP_VOLUME

#define PA_CLAMP_VOLUME ( v ) (PA_CLAMP_UNLIKELY((v), PA_VOLUME_MUTED, PA_VOLUME_MAX))

Clamp volume to the permitted range.

Since: 1.0

◆ pa_cvolume_is_muted

#define pa_cvolume_is_muted ( a ) pa_cvolume_channels_equal_to((a), PA_VOLUME_MUTED)

Return 1 if the specified volume has all channels muted.

◆ pa_cvolume_is_norm

#define pa_cvolume_is_norm ( a ) pa_cvolume_channels_equal_to((a), PA_VOLUME_NORM)

Return 1 if the specified volume has all channels on normal level.

◆ pa_cvolume_mute

#define pa_cvolume_mute	(	a,
		n
	)	pa_cvolume_set((a), (n), PA_VOLUME_MUTED)

Set the volume of the first n channels to PA_VOLUME_MUTED.

◆ pa_cvolume_reset

#define pa_cvolume_reset	(	a,
		n
	)	pa_cvolume_set((a), (n), PA_VOLUME_NORM)

Set the volume of the first n channels to PA_VOLUME_NORM.

◆ PA_CVOLUME_SNPRINT_MAX

#define PA_CVOLUME_SNPRINT_MAX 320

Maximum length of the strings returned by pa_cvolume_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.

◆ PA_CVOLUME_SNPRINT_VERBOSE_MAX

#define PA_CVOLUME_SNPRINT_VERBOSE_MAX 1984

Maximum length of the strings returned by pa_cvolume_snprint_verbose().

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.

Since: 5.0

◆ PA_DECIBEL_MININFTY

#define PA_DECIBEL_MININFTY ((double) -200.0)

This floor value is used as minus infinity when using pa_sw_volume_to_dB() / pa_sw_volume_from_dB().

◆ PA_SW_CVOLUME_SNPRINT_DB_MAX

#define PA_SW_CVOLUME_SNPRINT_DB_MAX 448

Maximum length of the strings returned by pa_sw_cvolume_snprint_dB().

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.

Since: 0.9.13

◆ PA_SW_VOLUME_SNPRINT_DB_MAX

#define PA_SW_VOLUME_SNPRINT_DB_MAX 11

Maximum length of the strings returned by pa_sw_volume_snprint_dB().

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.

Since: 0.9.15

◆ PA_VOLUME_INVALID

#define PA_VOLUME_INVALID ((pa_volume_t) UINT32_MAX)

Special 'invalid' volume.

Since: 0.9.16

◆ PA_VOLUME_IS_VALID

#define PA_VOLUME_IS_VALID ( v ) ((v) <= PA_VOLUME_MAX)

Check if volume is valid.

Since: 1.0

◆ PA_VOLUME_MAX

#define PA_VOLUME_MAX ((pa_volume_t) UINT32_MAX/2)

Maximum valid volume we can store.

Since: 0.9.15

◆ PA_VOLUME_MUTED

#define PA_VOLUME_MUTED ((pa_volume_t) 0U)

Muted (minimal valid) volume (0%, -inf dB)

◆ PA_VOLUME_NORM

#define PA_VOLUME_NORM ((pa_volume_t) 0x10000U)

Normal volume (100%, 0 dB)

◆ PA_VOLUME_SNPRINT_MAX

#define PA_VOLUME_SNPRINT_MAX 10

Maximum length of the strings returned by pa_volume_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.

Since: 0.9.15

◆ PA_VOLUME_SNPRINT_VERBOSE_MAX

#define PA_VOLUME_SNPRINT_VERBOSE_MAX 35

Maximum length of the strings returned by pa_volume_snprint_verbose().

Please note that this value can change with any release without warning and withou being considered API or ABI breakage. You should not use this definition anywhere where it might become part of an ABI.

Since: 5.0

◆ PA_VOLUME_UI_MAX

#define PA_VOLUME_UI_MAX (pa_sw_volume_from_dB(+11.0))

Recommended maximum volume to show in user facing UIs.

Note: UIs should deal gracefully with volumes greater than this value and not cause feedback loops etc. - i.e. if the volume is more than this, the UI should not limit it and push the limited value back to the server.

Since: 0.9.23

Typedef Documentation

◆ pa_cvolume

typedef struct pa_cvolume pa_cvolume

A structure encapsulating a per-channel volume.

◆ pa_volume_t

typedef uint32_t pa_volume_t

Volume specification: PA_VOLUME_MUTED: silence; < PA_VOLUME_NORM: decreased volume; PA_VOLUME_NORM: normal volume;

PA_VOLUME_NORM: increased volume

Function Documentation

◆ pa_cvolume_avg()

pa_volume_t pa_cvolume_avg ( const pa_cvolume * a )

Return the average volume of all channels.

◆ pa_cvolume_avg_mask()

pa_volume_t pa_cvolume_avg_mask	(	const pa_cvolume *	a,
		const pa_channel_map *	cm,
		pa_channel_position_mask_t	mask
	)

Return the average volume of all channels that are included in the specified channel map with the specified channel position mask.

If cm is NULL this call is identical to pa_cvolume_avg(). If no channel is selected the returned value will be PA_VOLUME_MUTED.

Since: 0.9.16

◆ pa_cvolume_channels_equal_to()

int pa_cvolume_channels_equal_to	(	const pa_cvolume *	a,
		pa_volume_t	v
	)

Return non-zero if the volume of all channels is equal to the specified value.

◆ pa_cvolume_compatible()

int pa_cvolume_compatible	(	const pa_cvolume *	v,
		const pa_sample_spec *	ss
	)

Return non-zero if the specified volume is compatible with the specified sample spec.

Since: 0.9.13

◆ pa_cvolume_compatible_with_channel_map()

int pa_cvolume_compatible_with_channel_map	(	const pa_cvolume *	v,
		const pa_channel_map *	cm
	)

Return non-zero if the specified volume is compatible with the specified sample spec.

Since: 0.9.15

◆ pa_cvolume_dec()

pa_cvolume* pa_cvolume_dec	(	pa_cvolume *	v,
		pa_volume_t	dec
	)

Decrease the volume passed in by 'dec'.

The proportions between the channels are kept. Returns v, or NULL on error.

Since: 0.9.16

◆ pa_cvolume_equal()

int pa_cvolume_equal	(	const pa_cvolume *	a,
		const pa_cvolume *	b
	)

Return non-zero when *a == *b, checking that both a and b have the same number of channels and that the volumes of channels in a equal those in b.

◆ pa_cvolume_get_balance()

float pa_cvolume_get_balance	(	const pa_cvolume *	v,
		const pa_channel_map *	map
	)

Calculate a 'balance' value for the specified volume with the specified channel map.

The return value will range from -1.0f (left) to +1.0f (right). If no balance value is applicable to this channel map the return value will always be 0.0f. See pa_channel_map_can_balance().

Since: 0.9.15

◆ pa_cvolume_get_fade()

float pa_cvolume_get_fade	(	const pa_cvolume *	v,
		const pa_channel_map *	map
	)

Calculate a 'fade' value (i.e. 'balance' between front and rear) for the specified volume with the specified channel map.

The return value will range from -1.0f (rear) to +1.0f (left). If no fade value is applicable to this channel map the return value will always be 0.0f. See pa_channel_map_can_fade().

Since: 0.9.15

◆ pa_cvolume_get_lfe_balance()

float pa_cvolume_get_lfe_balance	(	const pa_cvolume *	v,
		const pa_channel_map *	map
	)

Calculate a 'lfe balance' value for the specified volume with the specified channel map.

The return value will range from -1.0f (no lfe) to +1.0f (only lfe), where 0.0f is balanced. If no value is applicable to this channel map the return value will always be 0.0f. See pa_channel_map_can_lfe_balance().

Since: 8.0

◆ pa_cvolume_get_position()

pa_volume_t pa_cvolume_get_position	(	const pa_cvolume *	cv,
		const pa_channel_map *	map,
		pa_channel_position_t	t
	)

Get the maximum volume of all channels at the specified channel position.

Will return 0 if there is no channel at the position specified. You can check if a channel map includes a specific position by calling pa_channel_map_has_position().

Since: 0.9.16

◆ pa_cvolume_inc()

pa_cvolume* pa_cvolume_inc	(	pa_cvolume *	v,
		pa_volume_t	inc
	)

Increase the volume passed in by 'inc'.

The proportions between the channels are kept. Returns v, or NULL on error.

Since: 0.9.16

◆ pa_cvolume_inc_clamp()

pa_cvolume* pa_cvolume_inc_clamp	(	pa_cvolume *	v,
		pa_volume_t	inc,
		pa_volume_t	limit
	)

Increase the volume passed in by 'inc', but not exceeding 'limit'.

The proportions between the channels are kept. Returns v, or NULL on error.

Since: 0.9.19

◆ pa_cvolume_init()

pa_cvolume* pa_cvolume_init ( pa_cvolume * a )

Initialize the specified volume and return a pointer to it.

The sample spec will have a defined state but pa_cvolume_valid() will fail for it.

Since: 0.9.13

◆ pa_cvolume_max()

pa_volume_t pa_cvolume_max ( const pa_cvolume * a )

Return the maximum volume of all channels.

Since: 0.9.12

◆ pa_cvolume_max_mask()

pa_volume_t pa_cvolume_max_mask	(	const pa_cvolume *	a,
		const pa_channel_map *	cm,
		pa_channel_position_mask_t	mask
	)

Return the maximum volume of all channels that are included in the specified channel map with the specified channel position mask.

If cm is NULL this call is identical to pa_cvolume_max(). If no channel is selected the returned value will be PA_VOLUME_MUTED.

Since: 0.9.16

◆ pa_cvolume_merge()

pa_cvolume* pa_cvolume_merge	(	pa_cvolume *	dest,
		const pa_cvolume *	a,
		const pa_cvolume *	b
	)

This goes through all channels in a and b and sets the corresponding channel in dest to the greater volume of both.

a, b and dest may point to the same structure. Returns dest, or NULL on error.

Since: 0.9.16

◆ pa_cvolume_min()

pa_volume_t pa_cvolume_min ( const pa_cvolume * a )

Return the minimum volume of all channels.

Since: 0.9.16

◆ pa_cvolume_min_mask()

pa_volume_t pa_cvolume_min_mask	(	const pa_cvolume *	a,
		const pa_channel_map *	cm,
		pa_channel_position_mask_t	mask
	)

Return the minimum volume of all channels that are included in the specified channel map with the specified channel position mask.

If cm is NULL this call is identical to pa_cvolume_min(). If no channel is selected the returned value will be PA_VOLUME_MUTED.

Since: 0.9.16

◆ pa_cvolume_remap()

pa_cvolume* pa_cvolume_remap	(	pa_cvolume *	v,
		const pa_channel_map *	from,
		const pa_channel_map *	to
	)

Remap a volume from one channel mapping to a different channel mapping.

Returns v.

Since: 0.9.12

◆ pa_cvolume_scale()

pa_cvolume* pa_cvolume_scale	(	pa_cvolume *	v,
		pa_volume_t	max
	)

Scale the passed pa_cvolume structure so that the maximum volume of all channels equals max.

The proportions between the channel volumes are kept. Returns v, or NULL on error.

Since: 0.9.15

◆ pa_cvolume_scale_mask()

pa_cvolume* pa_cvolume_scale_mask	(	pa_cvolume *	v,
		pa_volume_t	max,
		const pa_channel_map *	cm,
		pa_channel_position_mask_t	mask
	)

Scale the passed pa_cvolume structure so that the maximum volume of all channels selected via cm/mask equals max.

This also modifies the volume of those channels that are unmasked. The proportions between the channel volumes are kept. If cm is NULL this call is identical to pa_cvolume_scale(). Returns v, or NULL on error.

Since: 0.9.16

◆ pa_cvolume_set()

pa_cvolume* pa_cvolume_set	(	pa_cvolume *	a,
		unsigned	channels,
		pa_volume_t	v
	)

Set the volume of the specified number of channels to the volume v.

◆ pa_cvolume_set_balance()

pa_cvolume* pa_cvolume_set_balance	(	pa_cvolume *	v,
		const pa_channel_map *	map,
		float	new_balance
	)

Adjust the 'balance' value for the specified volume with the specified channel map.

v will be modified in place and returned. The balance is a value between -1.0f and +1.0f. This operation might not be reversible! Also, after this call pa_cvolume_get_balance() is not guaranteed to actually return the requested balance value (e.g. when the input volume was zero anyway for all channels). If no balance value is applicable to this channel map the volume will not be modified. See pa_channel_map_can_balance(). Will return NULL on error.

Since: 0.9.15

◆ pa_cvolume_set_fade()

pa_cvolume* pa_cvolume_set_fade	(	pa_cvolume *	v,
		const pa_channel_map *	map,
		float	new_fade
	)

Adjust the 'fade' value (i.e. 'balance' between front and rear) for the specified volume with the specified channel map.

v will be modified in place and returned. The balance is a value between -1.0f and +1.0f. This operation might not be reversible! Also, after this call pa_cvolume_get_fade() is not guaranteed to actually return the requested fade value (e.g. when the input volume was zero anyway for all channels). If no fade value is applicable to this channel map the volume will not be modified. See pa_channel_map_can_fade(). Will return NULL on error.

Since: 0.9.15

◆ pa_cvolume_set_lfe_balance()

pa_cvolume* pa_cvolume_set_lfe_balance	(	pa_cvolume *	v,
		const pa_channel_map *	map,
		float	new_balance
	)

Adjust the 'lfe balance' value for the specified volume with the specified channel map.

v will be modified in place and returned. The balance is a value between -1.0f (no lfe) and +1.0f (only lfe). This operation might not be reversible! Also, after this call pa_cvolume_get_lfe_balance() is not guaranteed to actually return the requested value (e.g. when the input volume was zero anyway for all channels). If no lfe balance value is applicable to this channel map the volume will not be modified. See pa_channel_map_can_lfe_balance(). Will return NULL on error.

Since: 8.0

◆ pa_cvolume_set_position()

pa_cvolume* pa_cvolume_set_position	(	pa_cvolume *	cv,
		const pa_channel_map *	map,
		pa_channel_position_t	t,
		pa_volume_t	v
	)

Set the passed volume to all channels at the specified channel position.

Will return the updated volume struct, or NULL if there is no channel at the position specified. You can check if a channel map includes a specific position by calling pa_channel_map_has_position(). Returns cv, or NULL on error.

Since: 0.9.16

◆ pa_cvolume_snprint()

char* pa_cvolume_snprint	(	char *	s,
		size_t	l,
		const pa_cvolume *	c
	)

Pretty print a volume structure.

Returns s.

◆ pa_cvolume_snprint_verbose()

char* pa_cvolume_snprint_verbose	(	char *	s,
		size_t	l,
		const pa_cvolume *	c,
		const pa_channel_map *	map,
		int	print_dB
	)

Pretty print a volume structure in a verbose way.

The volume for each channel is printed in several formats: the raw pa_volume_t value, percentage, and if print_dB is non-zero, also the dB value. If map is not NULL, the channel names will be printed. Returns s.

Since: 5.0

◆ pa_cvolume_valid()

int pa_cvolume_valid ( const pa_cvolume * v )

Return non-zero when the passed cvolume structure is valid.

◆ pa_sw_cvolume_divide()

pa_cvolume* pa_sw_cvolume_divide	(	pa_cvolume *	dest,
		const pa_cvolume *	a,
		const pa_cvolume *	b
	)

Divide two per-channel volumes and return the result in *dest.

This is only valid for software volumes! a, b and dest may point to the same structure. Returns dest, or NULL on error.

Since: 0.9.13

◆ pa_sw_cvolume_divide_scalar()

pa_cvolume* pa_sw_cvolume_divide_scalar	(	pa_cvolume *	dest,
		const pa_cvolume *	a,
		pa_volume_t	b
	)

Divide a per-channel volume by a scalar volume and return the result in *dest.

This is only valid for software volumes! a and dest may point to the same structure. Returns dest, or NULL on error.

Since: 0.9.16

◆ pa_sw_cvolume_multiply()

pa_cvolume* pa_sw_cvolume_multiply	(	pa_cvolume *	dest,
		const pa_cvolume *	a,
		const pa_cvolume *	b
	)

Multiply two per-channel volumes and return the result in *dest.

This is only valid for software volumes! a, b and dest may point to the same structure. Returns dest, or NULL on error.

◆ pa_sw_cvolume_multiply_scalar()

pa_cvolume* pa_sw_cvolume_multiply_scalar	(	pa_cvolume *	dest,
		const pa_cvolume *	a,
		pa_volume_t	b
	)

Multiply a per-channel volume with a scalar volume and return the result in *dest.

This is only valid for software volumes! a and dest may point to the same structure. Returns dest, or NULL on error.

Since: 0.9.16

◆ pa_sw_cvolume_snprint_dB()

char* pa_sw_cvolume_snprint_dB	(	char *	s,
		size_t	l,
		const pa_cvolume *	c
	)

Pretty print a volume structure, showing dB values.

Returns s.

Since: 0.9.13

◆ pa_sw_volume_divide()

pa_volume_t pa_sw_volume_divide	(	pa_volume_t	a,
		pa_volume_t	b
	)

Divide two volume specifications, return the result.

This uses PA_VOLUME_NORM as neutral element of division. This is only valid for software volumes! If a division by zero is tried the result will be 0.

Since: 0.9.13

◆ pa_sw_volume_from_dB()

pa_volume_t pa_sw_volume_from_dB ( double f )

Convert a decibel value to a volume (amplitude, not power).

This is only valid for software volumes!

◆ pa_sw_volume_from_linear()

pa_volume_t pa_sw_volume_from_linear ( double v )

Convert a linear factor to a volume.

0.0 and less is muted while 1.0 is PA_VOLUME_NORM. This is only valid for software volumes!

◆ pa_sw_volume_multiply()

pa_volume_t pa_sw_volume_multiply	(	pa_volume_t	a,
		pa_volume_t	b
	)

Multiply two volume specifications, return the result.

This uses PA_VOLUME_NORM as neutral element of multiplication. This is only valid for software volumes!

◆ pa_sw_volume_snprint_dB()

char* pa_sw_volume_snprint_dB	(	char *	s,
		size_t	l,
		pa_volume_t	v
	)

Pretty print a volume but show dB values.

Returns s.

Since: 0.9.15

◆ pa_sw_volume_to_dB()

double pa_sw_volume_to_dB ( pa_volume_t v )

Convert a volume to a decibel value (amplitude, not power).

This is only valid for software volumes!

◆ pa_sw_volume_to_linear()

double pa_sw_volume_to_linear ( pa_volume_t v )

Convert a volume to a linear factor.

This is only valid for software volumes!

◆ pa_volume_snprint()

char* pa_volume_snprint	(	char *	s,
		size_t	l,
		pa_volume_t	v
	)

Pretty print a volume.

Returns s.

Since: 0.9.15

◆ pa_volume_snprint_verbose()

char* pa_volume_snprint_verbose	(	char *	s,
		size_t	l,
		pa_volume_t	v,
		int	print_dB
	)

Pretty print a volume in a verbose way.

The volume is printed in several formats: the raw pa_volume_t value, percentage, and if print_dB is non-zero, also the dB value. Returns s.

Since: 5.0

Data Structures

Macros

Typedefs

Functions

Detailed Description

Macro Definition Documentation

◆ PA_CLAMP_VOLUME

◆ pa_cvolume_is_muted

◆ pa_cvolume_is_norm

◆ pa_cvolume_mute

◆ pa_cvolume_reset

◆ PA_CVOLUME_SNPRINT_MAX

◆ PA_CVOLUME_SNPRINT_VERBOSE_MAX

◆ PA_DECIBEL_MININFTY

◆ PA_SW_CVOLUME_SNPRINT_DB_MAX

◆ PA_SW_VOLUME_SNPRINT_DB_MAX

◆ PA_VOLUME_INVALID

◆ PA_VOLUME_IS_VALID

◆ PA_VOLUME_MAX

◆ PA_VOLUME_MUTED

◆ PA_VOLUME_NORM

◆ PA_VOLUME_SNPRINT_MAX

◆ PA_VOLUME_SNPRINT_VERBOSE_MAX

◆ PA_VOLUME_UI_MAX

Typedef Documentation

◆ pa_cvolume

◆ pa_volume_t

Function Documentation

◆ pa_cvolume_avg()

◆ pa_cvolume_avg_mask()

◆ pa_cvolume_channels_equal_to()

◆ pa_cvolume_compatible()

◆ pa_cvolume_compatible_with_channel_map()

◆ pa_cvolume_dec()

◆ pa_cvolume_equal()

◆ pa_cvolume_get_balance()

◆ pa_cvolume_get_fade()

◆ pa_cvolume_get_lfe_balance()

◆ pa_cvolume_get_position()

◆ pa_cvolume_inc()

◆ pa_cvolume_inc_clamp()

◆ pa_cvolume_init()

◆ pa_cvolume_max()

◆ pa_cvolume_max_mask()

◆ pa_cvolume_merge()

◆ pa_cvolume_min()

◆ pa_cvolume_min_mask()

◆ pa_cvolume_remap()

◆ pa_cvolume_scale()

◆ pa_cvolume_scale_mask()

◆ pa_cvolume_set()

◆ pa_cvolume_set_balance()

◆ pa_cvolume_set_fade()

◆ pa_cvolume_set_lfe_balance()

◆ pa_cvolume_set_position()

◆ pa_cvolume_snprint()

◆ pa_cvolume_snprint_verbose()

◆ pa_cvolume_valid()

◆ pa_sw_cvolume_divide()

◆ pa_sw_cvolume_divide_scalar()

◆ pa_sw_cvolume_multiply()

◆ pa_sw_cvolume_multiply_scalar()

◆ pa_sw_cvolume_snprint_dB()

◆ pa_sw_volume_divide()

◆ pa_sw_volume_from_dB()

◆ pa_sw_volume_from_linear()

◆ pa_sw_volume_multiply()

◆ pa_sw_volume_snprint_dB()

◆ pa_sw_volume_to_dB()

◆ pa_sw_volume_to_linear()

◆ pa_volume_snprint()

◆ pa_volume_snprint_verbose()