PipeWire 1.0.5
Loading...
Searching...
No Matches
Stream

Files

file  stream.h
 pipewire/stream.h
 

Data Structures

struct  pw_buffer
 a buffer structure obtained from pw_stream_dequeue_buffer(). More...
 
struct  pw_stream_control
 
struct  pw_time
 A time structure. More...
 
struct  pw_stream_events
 Events for a stream. More...
 
struct  pw_stream
 

Enumerations

enum  pw_stream_state {
  PW_STREAM_STATE_ERROR = -1 , PW_STREAM_STATE_UNCONNECTED = 0 , PW_STREAM_STATE_CONNECTING = 1 , PW_STREAM_STATE_PAUSED = 2 ,
  PW_STREAM_STATE_STREAMING = 3
}
 The state of a stream. More...
 
enum  pw_stream_flags {
  PW_STREAM_FLAG_NONE = 0 , PW_STREAM_FLAG_AUTOCONNECT = (1 << 0) , PW_STREAM_FLAG_INACTIVE = (1 << 1) , PW_STREAM_FLAG_MAP_BUFFERS = (1 << 2) ,
  PW_STREAM_FLAG_DRIVER = (1 << 3) , PW_STREAM_FLAG_RT_PROCESS = (1 << 4) , PW_STREAM_FLAG_NO_CONVERT = (1 << 5) , PW_STREAM_FLAG_EXCLUSIVE = (1 << 6) ,
  PW_STREAM_FLAG_DONT_RECONNECT = (1 << 7) , PW_STREAM_FLAG_ALLOC_BUFFERS = (1 << 8) , PW_STREAM_FLAG_TRIGGER = (1 << 9) , PW_STREAM_FLAG_ASYNC = (1 << 10) ,
  PW_STREAM_FLAG_EARLY_PROCESS = (1 << 11)
}
 Extra flags that can be used in pw_stream_connect() More...
 

Macros

#define PW_VERSION_STREAM_EVENTS   2
 

Functions

const char * pw_stream_state_as_string (enum pw_stream_state state)
 Convert a stream state to a readable string.
 
struct pw_streampw_stream_new (struct pw_core *core, const char *name, struct pw_properties *props)
 Create a new unconneced Stream.
 
struct pw_streampw_stream_new_simple (struct pw_loop *loop, const char *name, struct pw_properties *props, const struct pw_stream_events *events, void *data)
 
void pw_stream_destroy (struct pw_stream *stream)
 Destroy a stream.
 
void pw_stream_add_listener (struct pw_stream *stream, struct spa_hook *listener, const struct pw_stream_events *events, void *data)
 
enum pw_stream_state pw_stream_get_state (struct pw_stream *stream, const char **error)
 
const char * pw_stream_get_name (struct pw_stream *stream)
 
struct pw_corepw_stream_get_core (struct pw_stream *stream)
 
const struct pw_propertiespw_stream_get_properties (struct pw_stream *stream)
 
int pw_stream_update_properties (struct pw_stream *stream, const struct spa_dict *dict)
 
int pw_stream_connect (struct pw_stream *stream, enum pw_direction direction, uint32_t target_id, enum pw_stream_flags flags, const struct spa_pod **params, uint32_t n_params)
 Connect a stream for input or output on port_path.
 
uint32_t pw_stream_get_node_id (struct pw_stream *stream)
 Get the node ID of the stream.
 
int pw_stream_disconnect (struct pw_stream *stream)
 Disconnect stream

 
int pw_stream_set_error (struct pw_stream *stream, int res, const char *error,...)
 Set the stream in error state.
 
int pw_stream_update_params (struct pw_stream *stream, const struct spa_pod **params, uint32_t n_params)
 Update the param exposed on the stream.
 
int pw_stream_set_param (struct pw_stream *stream, uint32_t id, const struct spa_pod *param)
 Set a parameter on the stream.
 
const struct pw_stream_controlpw_stream_get_control (struct pw_stream *stream, uint32_t id)
 Get control values.
 
int pw_stream_set_control (struct pw_stream *stream, uint32_t id, uint32_t n_values, float *values,...)
 Set control values.
 
int pw_stream_get_time_n (struct pw_stream *stream, struct pw_time *time, size_t size)
 Query the time on the stream.
 
uint64_t pw_stream_get_nsec (struct pw_stream *stream)
 Get the current time in nanoseconds.
 
int pw_stream_get_time (struct pw_stream *stream, struct pw_time *time)
 Query the time on the stream, deprecated since 0.3.50, use pw_stream_get_time_n() to get the fields added since 0.3.50.
 
struct pw_bufferpw_stream_dequeue_buffer (struct pw_stream *stream)
 Get a buffer that can be filled for playback streams or consumed for capture streams.
 
int pw_stream_queue_buffer (struct pw_stream *stream, struct pw_buffer *buffer)
 Submit a buffer for playback or recycle a buffer for capture.
 
int pw_stream_set_active (struct pw_stream *stream, bool active)
 Activate or deactivate the stream.
 
int pw_stream_flush (struct pw_stream *stream, bool drain)
 Flush a stream.
 
bool pw_stream_is_driving (struct pw_stream *stream)
 Check if the stream is driving.
 
int pw_stream_trigger_process (struct pw_stream *stream)
 Trigger a push/pull on the stream.
 

Detailed Description

PipeWire stream objects

The stream object provides a convenient way to send and receive data streams from/to PipeWire.

See also
Streams, Core API

Enumeration Type Documentation

◆ pw_stream_state

The state of a stream.

Enumerator
PW_STREAM_STATE_ERROR 

the stream is in error

PW_STREAM_STATE_UNCONNECTED 

unconnected

PW_STREAM_STATE_CONNECTING 

connection is in progress

PW_STREAM_STATE_PAUSED 

paused

PW_STREAM_STATE_STREAMING 

streaming

◆ pw_stream_flags

Extra flags that can be used in pw_stream_connect()

Enumerator
PW_STREAM_FLAG_NONE 

no flags

PW_STREAM_FLAG_AUTOCONNECT 

try to automatically connect this stream

PW_STREAM_FLAG_INACTIVE 

start the stream inactive, pw_stream_set_active() needs to be called explicitly

PW_STREAM_FLAG_MAP_BUFFERS 

mmap the buffers except DmaBuf that is not explicitly marked as mappable.

PW_STREAM_FLAG_DRIVER 

be a driver

PW_STREAM_FLAG_RT_PROCESS 

call process from the realtime thread.

You MUST use RT safe functions in the process callback.

PW_STREAM_FLAG_NO_CONVERT 

don't convert format

PW_STREAM_FLAG_EXCLUSIVE 

require exclusive access to the device

PW_STREAM_FLAG_DONT_RECONNECT 

don't try to reconnect this stream when the sink/source is removed

PW_STREAM_FLAG_ALLOC_BUFFERS 

the application will allocate buffer memory.

In the add_buffer event, the data of the buffer should be set

PW_STREAM_FLAG_TRIGGER 

the output stream will not be scheduled automatically but _trigger_process() needs to be called.

This can be used when the output of the stream depends on input from other streams.

PW_STREAM_FLAG_ASYNC 

Buffers will not be dequeued/queued from the realtime process() function.

This is assumed when RT_PROCESS is unset but can also be the case when the process() function does a trigger_process() that will then dequeue/queue a buffer from another process() function. since 0.3.73

PW_STREAM_FLAG_EARLY_PROCESS 

Call process as soon as there is a buffer to dequeue.

This is only relevant for playback and when not using RT_PROCESS. It can be used to keep the maximum number of buffers queued. Since 0.3.81

Macro Definition Documentation

◆ PW_VERSION_STREAM_EVENTS

Function Documentation

◆ pw_stream_state_as_string()

const char * pw_stream_state_as_string ( enum pw_stream_state state)

◆ pw_stream_new()

struct pw_stream * pw_stream_new ( struct pw_core * core,
const char * name,
struct pw_properties * props )

Create a new unconneced Stream.

Returns
a newly allocated Stream
Parameters
corea Core
namea stream media name
propsstream properties, ownership is taken
Examples
video-src.c.

◆ pw_stream_new_simple()

struct pw_stream * pw_stream_new_simple ( struct pw_loop * loop,
const char * name,
struct pw_properties * props,
const struct pw_stream_events * events,
void * data )
Parameters
loopa Loop to use
namea stream media name
propsstream properties, ownership is taken
eventsstream events
datadata passed to events
Examples
audio-capture.c, audio-src.c, tutorial4.c, tutorial5.c, video-play-fixate.c, video-play-pull.c, video-play-reneg.c, video-play.c, video-src-alloc.c, video-src-fixate.c, and video-src-reneg.c.

◆ pw_stream_destroy()

◆ pw_stream_add_listener()

void pw_stream_add_listener ( struct pw_stream * stream,
struct spa_hook * listener,
const struct pw_stream_events * events,
void * data )
Examples
video-src.c.

◆ pw_stream_get_state()

enum pw_stream_state pw_stream_get_state ( struct pw_stream * stream,
const char ** error )

◆ pw_stream_get_name()

const char * pw_stream_get_name ( struct pw_stream * stream)

◆ pw_stream_get_core()

struct pw_core * pw_stream_get_core ( struct pw_stream * stream)

◆ pw_stream_get_properties()

const struct pw_properties * pw_stream_get_properties ( struct pw_stream * stream)

◆ pw_stream_update_properties()

int pw_stream_update_properties ( struct pw_stream * stream,
const struct spa_dict * dict )

◆ pw_stream_connect()

int pw_stream_connect ( struct pw_stream * stream,
enum pw_direction direction,
uint32_t target_id,
enum pw_stream_flags flags,
const struct spa_pod ** params,
uint32_t n_params )

Connect a stream for input or output on port_path.

Returns
0 on success < 0 on error.

You should connect to the process event and use pw_stream_dequeue_buffer() to get the latest metadata and data.

Parameters
streama Stream
directionthe stream direction
target_idshould have the value PW_ID_ANY. To select a specific target node, specify the PW_KEY_OBJECT_SERIAL or the PW_KEY_NODE_NAME value of the target node in the PW_KEY_TARGET_OBJECT property of the stream. Specifying target nodes by their id is deprecated.
flagsstream flags
paramsan array with params. The params should ideally contain supported formats.
n_paramsnumber of items in params
Examples
audio-capture.c, audio-src.c, tutorial4.c, tutorial5.c, video-play-fixate.c, video-play-pull.c, video-play-reneg.c, video-play.c, video-src-alloc.c, video-src-fixate.c, video-src-reneg.c, and video-src.c.

◆ pw_stream_get_node_id()

uint32_t pw_stream_get_node_id ( struct pw_stream * stream)

Get the node ID of the stream.

Returns
node ID.
Examples
video-src-alloc.c, video-src-fixate.c, video-src-reneg.c, and video-src.c.

◆ pw_stream_disconnect()

int pw_stream_disconnect ( struct pw_stream * stream)

Disconnect stream

◆ pw_stream_set_error()

int pw_stream_set_error ( struct pw_stream * stream,
int res,
const char * error,
... )

Set the stream in error state.

Parameters
streama Stream
resa result code
erroran error message
Examples
video-play-fixate.c, video-play-pull.c, video-play-reneg.c, and video-play.c.

◆ pw_stream_update_params()

int pw_stream_update_params ( struct pw_stream * stream,
const struct spa_pod ** params,
uint32_t n_params )

Update the param exposed on the stream.

Parameters
streama Stream
paramsan array of params.
n_paramsnumber of elements in params
Examples
video-play-fixate.c, video-play-pull.c, video-play-reneg.c, video-play.c, video-src-alloc.c, video-src-fixate.c, video-src-reneg.c, and video-src.c.

◆ pw_stream_set_param()

int pw_stream_set_param ( struct pw_stream * stream,
uint32_t id,
const struct spa_pod * param )

Set a parameter on the stream.

This is like pw_stream_set_control() but with a complete spa_pod param. It can also be called from the param_changed event handler to intercept and modify the param for the adapter. Since 0.3.70

Parameters
streama Stream
idthe id of the param
paramthe params to set

◆ pw_stream_get_control()

const struct pw_stream_control * pw_stream_get_control ( struct pw_stream * stream,
uint32_t id )

Get control values.

◆ pw_stream_set_control()

int pw_stream_set_control ( struct pw_stream * stream,
uint32_t id,
uint32_t n_values,
float * values,
... )

Set control values.

◆ pw_stream_get_time_n()

int pw_stream_get_time_n ( struct pw_stream * stream,
struct pw_time * time,
size_t size )

Query the time on the stream.

◆ pw_stream_get_nsec()

uint64_t pw_stream_get_nsec ( struct pw_stream * stream)

Get the current time in nanoseconds.

This value can be compared with the pw_time_now value. Since 1.0.4

Examples
video-src-alloc.c, video-src-fixate.c, video-src-reneg.c, and video-src.c.

◆ pw_stream_get_time()

int pw_stream_get_time ( struct pw_stream * stream,
struct pw_time * time )

Query the time on the stream, deprecated since 0.3.50, use pw_stream_get_time_n() to get the fields added since 0.3.50.

◆ pw_stream_dequeue_buffer()

struct pw_buffer * pw_stream_dequeue_buffer ( struct pw_stream * stream)

Get a buffer that can be filled for playback streams or consumed for capture streams.

Examples
audio-capture.c, audio-src.c, tutorial4.c, tutorial5.c, video-play-fixate.c, video-play-pull.c, video-play-reneg.c, video-play.c, video-src-alloc.c, video-src-fixate.c, video-src-reneg.c, and video-src.c.

◆ pw_stream_queue_buffer()

int pw_stream_queue_buffer ( struct pw_stream * stream,
struct pw_buffer * buffer )

◆ pw_stream_set_active()

int pw_stream_set_active ( struct pw_stream * stream,
bool active )

Activate or deactivate the stream.

Examples
video-play.c.

◆ pw_stream_flush()

int pw_stream_flush ( struct pw_stream * stream,
bool drain )

Flush a stream.

When drain is true, the drained callback will be called when all data is played or recorded

◆ pw_stream_is_driving()

bool pw_stream_is_driving ( struct pw_stream * stream)

Check if the stream is driving.

The stream needs to have the PW_STREAM_FLAG_DRIVER set. When the stream is driving, pw_stream_trigger_process() needs to be called when data is available (output) or needed (input). Since 0.3.34

Examples
video-src-alloc.c, video-src-fixate.c, and video-src-reneg.c.

◆ pw_stream_trigger_process()

int pw_stream_trigger_process ( struct pw_stream * stream)

Trigger a push/pull on the stream.

One iteration of the graph will scheduled and process() will be called. Since 0.3.34

Examples
video-play-pull.c, video-src-alloc.c, video-src-fixate.c, video-src-reneg.c, and video-src.c.