PCM Plugins

Files
file	pcm_hw.c
	PCM HW Plugin Interface.
file	pcm_mmap_emul.c
	PCM Mmap-Emulation Plugin Interface.
file	pcm_shm.c
	PCM Shared Memory Plugin Interface.
file	pcm_null.c
	PCM Null Plugin Interface.
file	pcm_copy.c
	PCM Copy Plugin Interface.
file	pcm_linear.c
	PCM Linear Conversion Plugin Interface.
file	pcm_lfloat.c
	PCM Linear<->Float Conversion Plugin Interface.
file	pcm_mulaw.c
	PCM Mu-Law Conversion Plugin Interface.
file	pcm_alaw.c
	PCM A-Law Conversion Plugin Interface.
file	pcm_adpcm.c
	PCM Ima-ADPCM Conversion Plugin Interface.
file	pcm_route.c
	PCM Route & Volume Plugin Interface.
file	pcm_rate.c
	PCM Rate Plugin Interface.
file	pcm_file.c
	PCM File Plugin Interface.
file	pcm_multi.c
	PCM Multi Streams to One Conversion Plugin Interface.
file	pcm_share.c
	PCM Share Plugin Interface.
file	pcm_dmix.c
	PCM Direct Stream Mixing (dmix) Plugin Interface.
file	pcm_dshare.c
	PCM Direct Sharing of Channels Plugin Interface.
file	pcm_dsnoop.c
	PCM Capture Stream Snooping (dsnoop) Plugin Interface.
file	pcm_ladspa.c
	ALSA Plugin <-> LADSPA Plugin Interface.
file	pcm_asym.c
	PCM Asymmetrical Plugin Interface.
file	pcm_iec958.c
	PCM IEC958 Subframe Conversion Plugin Interface.
file	pcm_softvol.c
	PCM Soft Volume Plugin Interface.
file	pcm_empty.c
	PCM Empty Plugin Interface.

Macros
#define	SND_PCM_PLUGIN_RATE_MIN   4000
#define	SND_PCM_PLUGIN_RATE_MAX   768000
#define	SND_PCM_PLUGIN_ROUTE_FLOAT   1
#define	SND_PCM_PLUGIN_ROUTE_RESOLUTION   16
#define	SND_PCM_PLUGIN_ROUTE_HALF   (SND_PCM_PLUGIN_ROUTE_RESOLUTION / 2)
#define	SND_PCM_PLUGIN_ROUTE_FULL   SND_PCM_PLUGIN_ROUTE_RESOLUTION

Typedefs
typedef int	snd_pcm_route_ttable_entry_t

Functions
int	snd_pcm_hw_open (snd_pcm_t **pcmp, const char *name, int card, int device, int subdevice, snd_pcm_stream_t stream, int mode, int mmap_emulation, int sync_ptr_ioctl)
	Creates a new hw PCM.
int	_snd_pcm_hw_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new hw PCM.
int	snd_pcm_copy_open (snd_pcm_t **pcmp, const char *name, snd_pcm_t *slave, int close_slave)
	Creates a new copy PCM.
int	_snd_pcm_copy_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new copy PCM.
int	snd_pcm_linear_open (snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, snd_pcm_t *slave, int close_slave)
	Creates a new linear conversion PCM.
int	_snd_pcm_linear_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new linear conversion PCM.
int	snd_pcm_lfloat_open (snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, snd_pcm_t *slave, int close_slave)
	Creates a new linear conversion PCM.
int	_snd_pcm_lfloat_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new linear<->float conversion PCM.
int	snd_pcm_mulaw_open (snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, snd_pcm_t *slave, int close_slave)
	Creates a new Mu-Law conversion PCM.
int	_snd_pcm_mulaw_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new Mu-Law conversion PCM.
int	snd_pcm_alaw_open (snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, snd_pcm_t *slave, int close_slave)
	Creates a new A-Law conversion PCM.
int	_snd_pcm_alaw_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new A-Law conversion PCM.
int	snd_pcm_adpcm_open (snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, snd_pcm_t *slave, int close_slave)
	Creates a new Ima-ADPCM conversion PCM.
int	_snd_pcm_adpcm_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new Ima-ADPCM conversion PCM.
int	snd_pcm_iec958_open (snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, snd_pcm_t *slave, int close_slave, const unsigned char *status_bits, const unsigned char *preamble_vals, int hdmi_mode)
	Creates a new IEC958 subframe conversion PCM.
int	_snd_pcm_iec958_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new IEC958 subframe conversion PCM.
int	snd_pcm_route_load_ttable (snd_config_t *tt, snd_pcm_route_ttable_entry_t *ttable, unsigned int tt_csize, unsigned int tt_ssize, unsigned int *tt_cused, unsigned int *tt_sused, int schannels)
	Load route matrix.
int	snd_pcm_route_determine_ttable (snd_config_t *tt, unsigned int *tt_csize, unsigned int *tt_ssize)
	Determine route matrix sizes.
int	snd_pcm_route_open (snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, int schannels, snd_pcm_route_ttable_entry_t *ttable, unsigned int tt_ssize, unsigned int tt_cused, unsigned int tt_sused, snd_pcm_t *slave, int close_slave)
	Creates a new Route & Volume PCM.
int	_snd_pcm_route_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new Route & Volume PCM.
int	snd_pcm_rate_open (snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat, unsigned int srate, const snd_config_t *converter, snd_pcm_t *slave, int close_slave)
	Creates a new rate PCM.
int	_snd_pcm_rate_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new rate PCM.
int	snd_pcm_hooks_open (snd_pcm_t **pcmp, const char *name, snd_pcm_t *slave, int close_slave)
	Creates a new hooks PCM.
int	_snd_pcm_hooks_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new hooks PCM.
int	snd_pcm_ladspa_open (snd_pcm_t **pcmp, const char *name, const char *ladspa_path, unsigned int channels, snd_config_t *ladspa_pplugins, snd_config_t *ladspa_cplugins, snd_pcm_t *slave, int close_slave)
	Creates a new LADSPA<->ALSA Plugin.
int	_snd_pcm_ladspa_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new LADSPA<->ALSA PCM.
int	snd_pcm_jack_open (snd_pcm_t **pcmp, const char *name, snd_config_t *playback_conf, snd_config_t *capture_conf, snd_pcm_stream_t stream, int mode)
	Creates a new Jack PCM.
int	_snd_pcm_jack_open (snd_pcm_t **pcmp, const char *name, snd_config_t *root, snd_config_t *conf, snd_pcm_stream_t stream, int mode)
	Creates a new Jack PCM (internal)

Detailed Description

See the PCM (digital audio) plugins page for more details.

Macro Definition Documentation

SND_PCM_PLUGIN_RATE_MAX

#define SND_PCM_PLUGIN_RATE_MAX   768000

maximal rate for the rate plugin

SND_PCM_PLUGIN_RATE_MIN

#define SND_PCM_PLUGIN_RATE_MIN   4000

minimal rate for the rate plugin

SND_PCM_PLUGIN_ROUTE_FLOAT

#define SND_PCM_PLUGIN_ROUTE_FLOAT   1

use floats for route plugin

SND_PCM_PLUGIN_ROUTE_FULL

#define SND_PCM_PLUGIN_ROUTE_FULL   SND_PCM_PLUGIN_ROUTE_RESOLUTION

full value

SND_PCM_PLUGIN_ROUTE_HALF

#define SND_PCM_PLUGIN_ROUTE_HALF   (SND_PCM_PLUGIN_ROUTE_RESOLUTION / 2)

half value

SND_PCM_PLUGIN_ROUTE_RESOLUTION

#define SND_PCM_PLUGIN_ROUTE_RESOLUTION   16

integer resolution for route plugin

Typedef Documentation

snd_pcm_route_ttable_entry_t

typedef int snd_pcm_route_ttable_entry_t

route ttable entry type

Function Documentation

_snd_pcm_adpcm_open()

int _snd_pcm_adpcm_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new Ima-ADPCM conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with copy PCM description
stream	Stream type
mode	Stream mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_alaw_open()

int _snd_pcm_alaw_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new A-Law conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with copy PCM description
stream	Stream type
mode	Stream mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_copy_open()

int _snd_pcm_copy_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new copy PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with copy PCM description
stream	Stream type
mode	Stream mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_hooks_open()

int _snd_pcm_hooks_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new hooks PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with hooks PCM description
stream	PCM Stream
mode	PCM Mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_hw_open()

int _snd_pcm_hw_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new hw PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with hw PCM description
stream	PCM Stream
mode	PCM Mode

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_iec958_open()

int _snd_pcm_iec958_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new IEC958 subframe conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with copy PCM description
stream	Stream type
mode	Stream mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_jack_open()

int _snd_pcm_jack_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new Jack PCM (internal)

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration for this PCM
stream	Stream direction
mode	PCM open mode

Return values

zero	on success otherwise a negative error code

Warning

alsa-lib must be compiled against the JACK library for this plugin to be available

_snd_pcm_ladspa_open()

int _snd_pcm_ladspa_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new LADSPA<->ALSA PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with LADSPA<->ALSA PCM description
stream	Stream type
mode	Stream mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_lfloat_open()

int _snd_pcm_lfloat_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new linear<->float conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with copy PCM description
stream	Stream type
mode	Stream mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_linear_open()

int _snd_pcm_linear_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new linear conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with copy PCM description
stream	Stream type
mode	Stream mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_mulaw_open()

int _snd_pcm_mulaw_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new Mu-Law conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with copy PCM description
stream	Stream type
mode	Stream mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_rate_open()

int _snd_pcm_rate_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new rate PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with rate PCM description
stream	Stream type
mode	Stream mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

_snd_pcm_route_open()

int _snd_pcm_route_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	root,
		snd_config_t *	conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new Route & Volume PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
root	Root configuration node
conf	Configuration node with Route & Volume PCM description
stream	Stream type
mode	Stream mode

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_adpcm_open()

int snd_pcm_adpcm_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_pcm_format_t	sformat,
		snd_pcm_t *	slave,
		int	close_slave )

Creates a new Ima-ADPCM conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
sformat	Slave (destination) format
slave	Slave PCM handle
close_slave	When set, the slave PCM handle is closed with copy PCM

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_alaw_open()

int snd_pcm_alaw_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_pcm_format_t	sformat,
		snd_pcm_t *	slave,
		int	close_slave )

Creates a new A-Law conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
sformat	Slave (destination) format
slave	Slave PCM handle
close_slave	When set, the slave PCM handle is closed with copy PCM

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_copy_open()

int snd_pcm_copy_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_pcm_t *	slave,
		int	close_slave )

Creates a new copy PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
slave	Slave PCM handle
close_slave	When set, the slave PCM handle is closed with copy PCM

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_hooks_open()

int snd_pcm_hooks_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_pcm_t *	slave,
		int	close_slave )

Creates a new hooks PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
slave	Slave PCM
close_slave	If set, slave PCM handle is closed when hooks PCM is closed

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_hw_open()

int snd_pcm_hw_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		int	card,
		int	device,
		int	subdevice,
		snd_pcm_stream_t	stream,
		int	mode,
		int	mmap_emulation,
		int	sync_ptr_ioctl )

Creates a new hw PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
card	Number of card
device	Number of device
subdevice	Number of subdevice
stream	PCM Stream
mode	PCM Mode
mmap_emulation	Obsoleted parameter
sync_ptr_ioctl	Use SYNC_PTR ioctl rather than mmap for control structures

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_iec958_open()

int snd_pcm_iec958_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_pcm_format_t	sformat,
		snd_pcm_t *	slave,
		int	close_slave,
		const unsigned char *	status_bits,
		const unsigned char *	preamble_vals,
		int	hdmi_mode )

Creates a new IEC958 subframe conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
sformat	Slave (destination) format
slave	Slave PCM handle
close_slave	When set, the slave PCM handle is closed with copy PCM
status_bits	The IEC958 status bits
preamble_vals	The preamble byte values
hdmi_mode	When set, enable HDMI compliant formatting

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_jack_open()

int snd_pcm_jack_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_config_t *	playback_conf,
		snd_config_t *	capture_conf,
		snd_pcm_stream_t	stream,
		int	mode )

Creates a new Jack PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
playback_conf	Playback configuration
capture_conf	Capture configuration
stream	Stream direction
mode	PCM open mode

Return values

zero	on success otherwise a negative error code

Warning

alsa-lib must be compiled against the JACK library for this plugin to be available

snd_pcm_ladspa_open()

int snd_pcm_ladspa_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		const char *	ladspa_path,
		unsigned int	channels,
		snd_config_t *	ladspa_pplugins,
		snd_config_t *	ladspa_cplugins,
		snd_pcm_t *	slave,
		int	close_slave )

Creates a new LADSPA<->ALSA Plugin.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
ladspa_path	The path for LADSPA plugins
channels	Force input channel count to LADSPA plugin chain, 0 = no force (auto)
ladspa_pplugins	The playback configuration
ladspa_cplugins	The capture configuration
slave	Slave PCM handle
close_slave	When set, the slave PCM handle is closed with copy PCM

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_lfloat_open()

int snd_pcm_lfloat_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_pcm_format_t	sformat,
		snd_pcm_t *	slave,
		int	close_slave )

Creates a new linear conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
sformat	Slave (destination) format
slave	Slave PCM handle
close_slave	When set, the slave PCM handle is closed with copy PCM

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_linear_open()

int snd_pcm_linear_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_pcm_format_t	sformat,
		snd_pcm_t *	slave,
		int	close_slave )

Creates a new linear conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
sformat	Slave (destination) format
slave	Slave PCM handle
close_slave	When set, the slave PCM handle is closed with copy PCM

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_mulaw_open()

int snd_pcm_mulaw_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_pcm_format_t	sformat,
		snd_pcm_t *	slave,
		int	close_slave )

Creates a new Mu-Law conversion PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
sformat	Slave (destination) format
slave	Slave PCM handle
close_slave	When set, the slave PCM handle is closed with copy PCM

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_rate_open()

int snd_pcm_rate_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_pcm_format_t	sformat,
		unsigned int	srate,
		const snd_config_t *	converter,
		snd_pcm_t *	slave,
		int	close_slave )

Creates a new rate PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
sformat	Slave format
srate	Slave rate
converter	SRC type string node
slave	Slave PCM handle
close_slave	When set, the slave PCM handle is closed with copy PCM

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.

snd_pcm_route_determine_ttable()

int snd_pcm_route_determine_ttable	(	snd_config_t *	tt,
		unsigned int *	tt_csize,
		unsigned int *	tt_ssize )

Determine route matrix sizes.

Parameters

tt	Configuration root describing route matrix
tt_csize	Returned client size in elements
tt_ssize	Returned slave size in elements

Return values

zero	on success otherwise a negative error code

snd_pcm_route_load_ttable()

int snd_pcm_route_load_ttable	(	snd_config_t *	tt,
		snd_pcm_route_ttable_entry_t *	ttable,
		unsigned int	tt_csize,
		unsigned int	tt_ssize,
		unsigned int *	tt_cused,
		unsigned int *	tt_sused,
		int	schannels )

Load route matrix.

Parameters

tt	Configuration root describing route matrix
ttable	Returned route matrix
tt_csize	Client size in elements
tt_ssize	Slave size in elements
tt_cused	Used client elements
tt_sused	Used slave elements
schannels	Slave channels

Return values

zero	on success otherwise a negative error code

snd_pcm_route_open()

int snd_pcm_route_open	(	snd_pcm_t **	pcmp,
		const char *	name,
		snd_pcm_format_t	sformat,
		int	schannels,
		snd_pcm_route_ttable_entry_t *	ttable,
		unsigned int	tt_ssize,
		unsigned int	tt_cused,
		unsigned int	tt_sused,
		snd_pcm_t *	slave,
		int	close_slave )

Creates a new Route & Volume PCM.

Parameters

pcmp	Returns created PCM handle
name	Name of PCM
sformat	Slave format
schannels	Slave channels
ttable	Attenuation table
tt_ssize	Attenuation table - slave size
tt_cused	Attenuation table - client used count
tt_sused	Attenuation table - slave used count
slave	Slave PCM handle
close_slave	When set, the slave PCM handle is closed with copy PCM

Return values

zero	on success otherwise a negative error code

Warning

Using of this function might be dangerous in the sense of compatibility reasons. The prototype might be freely changed in future.