GStreamer Base Plugins 1.0 Library Reference Manual: gstaudiobasesink

## gstaudiobasesink gstaudiobasesink — Base class for audio sinks |

## Functions

#define | GST_AUDIO_BASE_SINK_CLOCK()
#define | GST_AUDIO_BASE_SINK_PAD()
GstAudioRingBuffer * | gst_audio_base_sink_create_ringbuffer ()
void | gst_audio_base_sink_set_provide_clock ()
gboolean | gst_audio_base_sink_get_provide_clock ()
void | gst_audio_base_sink_set_slave_method ()
GstAudioBaseSinkSlaveMethod | gst_audio_base_sink_get_slave_method ()
void | gst_audio_base_sink_set_drift_tolerance ()
gint64 | gst_audio_base_sink_get_drift_tolerance ()
void | gst_audio_base_sink_set_alignment_threshold ()
GstClockTime | gst_audio_base_sink_get_alignment_threshold ()
void | gst_audio_base_sink_set_discont_wait ()
GstClockTime | gst_audio_base_sink_get_discont_wait ()

## Properties

guint64 | alignment-threshold | Read / Write
gint64 | buffer-time | Read / Write
gboolean | can-activate-pull | Read / Write
guint64 | discont-wait | Read / Write
gint64 | drift-tolerance | Read / Write
gint64 | latency-time | Read / Write
gboolean | provide-clock | Read / Write
GstAudioBaseSinkSlaveMethod | slave-method | Read / Write

## Types and Values

struct | GstAudioBaseSink
struct | GstAudioBaseSinkClass
enum | GstAudioBaseSinkSlaveMethod

## Object Hierarchy

        GObject
        ╰── GInitiallyUnowned
            ╰── GstObject
                ╰── GstElement
                    ╰── GstBaseSink
                        ╰── GstAudioBaseSink
                            ╰── GstAudioSink

## Includes

    #include <gst/audio/gstaudiobasesink.h>

## Description

This is the base class for audio sinks. Subclasses need to implement the ::create_ringbuffer vmethod. This base class will then take care of writing samples to the ringbuffer, synchronisation, clipping and flushing.

## Functions

### GST_AUDIO_BASE_SINK_CLOCK()

    #define GST_AUDIO_BASE_SINK_CLOCK(obj)   (GST_AUDIO_BASE_SINK (obj)->clock)

Get the GstClock of `obj` .

#### Parameters

obj | a GstAudioBaseSink |

### GST_AUDIO_BASE_SINK_PAD()

    #define GST_AUDIO_BASE_SINK_PAD(obj)     (GST_BASE_SINK (obj)->sinkpad)

Get the sink GstPad of `obj` .

#### Parameters

obj | a GstAudioBaseSink |

### gst_audio_base_sink_create_ringbuffer ()

    GstAudioRingBuffer *
    gst_audio_base_sink_create_ringbuffer (GstAudioBaseSink *sink);

Create and return the GstAudioRingBuffer for `sink` . This function will call the ::create_ringbuffer vmethod and will set `sink` as the parent of the returned buffer (see `gst_object_set_parent()`).

#### Parameters

sink | a GstAudioBaseSink. |

#### Returns

The new ringbuffer of `sink` .

[transfer none]

### gst_audio_base_sink_set_provide_clock ()

    void
    gst_audio_base_sink_set_provide_clock (GstAudioBaseSink *sink,
                                           gboolean provide);

Controls whether `sink` will provide a clock or not. If `provide` is `TRUE`, `gst_element_provide_clock()` will return a clock that reflects the datarate of `sink` . If `provide` is `FALSE`, `gst_element_provide_clock()` will return NULL.

#### Parameters

sink | a GstAudioBaseSink |
provide | new state |

### gst_audio_base_sink_get_provide_clock ()

    gboolean
    gst_audio_base_sink_get_provide_clock (GstAudioBaseSink *sink);

Queries whether `sink` will provide a clock or not. See also gst_audio_base_sink_set_provide_clock.

#### Parameters

sink | a GstAudioBaseSink |

#### Returns

`TRUE` if `sink` will provide a clock.

### gst_audio_base_sink_set_slave_method ()

    void
    gst_audio_base_sink_set_slave_method (GstAudioBaseSink *sink,
                                          GstAudioBaseSinkSlaveMethod method);

Controls how clock slaving will be performed in `sink` .

#### Parameters

sink | a GstAudioBaseSink |
method | the new slave method |

### gst_audio_base_sink_get_slave_method ()

    GstAudioBaseSinkSlaveMethod
    gst_audio_base_sink_get_slave_method (GstAudioBaseSink *sink);

Get the current slave method used by `sink` .

#### Parameters

sink | a GstAudioBaseSink |

#### Returns

The current slave method used by `sink` .

### gst_audio_base_sink_set_drift_tolerance ()

    void
    gst_audio_base_sink_set_drift_tolerance
                                   (GstAudioBaseSink *sink,
                                    gint64 drift_tolerance);

Controls the sink's drift tolerance.

#### Parameters

sink | a GstAudioBaseSink |
drift_tolerance | the new drift tolerance in microseconds |

### gst_audio_base_sink_get_drift_tolerance ()

    gint64
    gst_audio_base_sink_get_drift_tolerance
                                   (GstAudioBaseSink *sink);

Get the current drift tolerance, in microseconds, used by `sink` .

#### Parameters

sink | a GstAudioBaseSink |

#### Returns

The current drift tolerance used by `sink` .

### gst_audio_base_sink_set_alignment_threshold ()

    void
    gst_audio_base_sink_set_alignment_threshold
                                   (GstAudioBaseSink *sink,
                                    GstClockTime alignment_threshold);

Controls the sink's alignment threshold.

#### Parameters

sink | a GstAudioBaseSink |
alignment_threshold | the new alignment threshold in nanoseconds |

### gst_audio_base_sink_get_alignment_threshold ()

    GstClockTime
    gst_audio_base_sink_get_alignment_threshold
                                   (GstAudioBaseSink *sink);

Get the current alignment threshold, in nanoseconds, used by `sink` .

#### Parameters

sink | a GstAudioBaseSink |

#### Returns

The current alignment threshold used by `sink` .

### gst_audio_base_sink_set_discont_wait ()

    void
    gst_audio_base_sink_set_discont_wait (GstAudioBaseSink *sink,
                                          GstClockTime discont_wait);

Controls how long the sink will wait before creating a discontinuity.

#### Parameters

sink | a GstAudioBaseSink |
discont_wait | the new discont wait in nanoseconds |

### gst_audio_base_sink_get_discont_wait ()

    GstClockTime
    gst_audio_base_sink_get_discont_wait (GstAudioBaseSink *sink);

Get the current discont wait, in nanoseconds, used by `sink` .

#### Parameters

sink | a GstAudioBaseSink |

#### Returns

The current discont wait used by `sink` .

## Types and Values

### struct GstAudioBaseSink

    struct GstAudioBaseSink;

Opaque GstAudioBaseSink.

### struct GstAudioBaseSinkClass

    struct GstAudioBaseSinkClass {
      GstBaseSinkClass     parent_class;

      /* subclass ringbuffer allocation */
      GstAudioRingBuffer* (*create_ringbuffer)  (GstAudioBaseSink *sink);

      /* subclass payloader */
      GstBuffer*          (*payload)            (GstAudioBaseSink *sink,
                                                 GstBuffer        *buffer);
    };

GstAudioBaseSink class. Override the vmethod to implement functionality.

#### Members

GstBaseSinkClass `parent_class`; | the parent class. |
`create_ringbuffer` () | create and return a GstAudioRingBuffer to write to. |
`payload` () | payload data in a format suitable to write to the sink. If no payloading is required, returns a reffed copy of the original buffer, else returns the payloaded buffer with all other metadata copied. |

### enum GstAudioBaseSinkSlaveMethod

Different possible clock slaving algorithms used when the internal audio clock is not selected as the pipeline master clock.

#### Members

GST_AUDIO_BASE_SINK_SLAVE_RESAMPLE | Resample to match the master clock |
GST_AUDIO_BASE_SINK_SLAVE_SKEW | Adjust playout pointer when master clock drifts too much. |
GST_AUDIO_BASE_SINK_SLAVE_NONE | No adjustment is done. |

## Property Details

### The `“alignment-threshold”` property

      “alignment-threshold”      guint64

Timestamp alignment threshold in nanoseconds.

Flags: Read / Write

Allowed values: [1,18446744073709551614]

Default value: 40000000

### The `“buffer-time”` property

      “buffer-time”              gint64

Size of audio buffer in microseconds, this is the minimum latency that the sink reports.

Flags: Read / Write

Allowed values: >= 1

Default value: 200000

### The `“can-activate-pull”` property

      “can-activate-pull”        gboolean

Allow pull-based scheduling.

Flags: Read / Write

Default value: FALSE

### The `“discont-wait”` property

      “discont-wait”             guint64

A window of time in nanoseconds to wait before creating a discontinuity as a result of breaching the drift-tolerance.

Flags: Read / Write

Allowed values: <= 18446744073709551614

Default value: 1000000000

### The `“drift-tolerance”` property

      “drift-tolerance”          gint64

Controls the amount of time in microseconds that clocks are allowed to drift before resynchronisation happens.

Flags: Read / Write

Allowed values: >= 1

Default value: 40000

### The `“latency-time”` property

      “latency-time”             gint64

The minimum amount of data to write in each iteration in microseconds.

Flags: Read / Write

Allowed values: >= 1

Default value: 10000

### The `“provide-clock”` property

      “provide-clock”            gboolean

Provide a clock to be used as the global pipeline clock.

Flags: Read / Write

Default value: TRUE

### The `“slave-method”` property

      “slave-method”             GstAudioBaseSinkSlaveMethod

Algorithm used to match the rate of the masterclock.

Flags: Read / Write

Default value: GST_AUDIO_BASE_SINK_SLAVE_SKEW

## See Also

GstAudioSink, GstAudioRingBuffer.