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GstTestClock is an implementation of #GstClock which has different behaviour compared to #GstSystemClock. Time for #GstSystemClock advances according to the system time, while time for #GstTestClock changes only when gst_test_clock_set_time() or gst_test_clock_advance_time() are called. #GstTestClock provides unit tests with the possibility to precisely advance the time in a deterministic manner, independent of the system time or any other external factors.

Advancing the time of a #GstTestClock

  #include <gst/gst.h>
#include <gst/check/gsttestclock.h>

GstClock *clock;
GstTestClock *test_clock;

clock = gst_test_clock_new ();
test_clock = GST_TEST_CLOCK (clock);
GST_INFO ("Time: %" GST_TIME_FORMAT, GST_TIME_ARGS (gst_clock_get_time (clock)));
gst_test_clock_advance_time ( test_clock, 1 * GST_SECOND);
GST_INFO ("Time: %" GST_TIME_FORMAT, GST_TIME_ARGS (gst_clock_get_time (clock)));
g_usleep (10 * G_USEC_PER_SEC);
GST_INFO ("Time: %" GST_TIME_FORMAT, GST_TIME_ARGS (gst_clock_get_time (clock)));
gst_test_clock_set_time (test_clock, 42 * GST_SECOND);
GST_INFO ("Time: %" GST_TIME_FORMAT, GST_TIME_ARGS (gst_clock_get_time (clock)));
...

#GstClock allows for setting up single shot or periodic clock notifications as well as waiting for these notifications synchronously (using gst_clock_id_wait()) or asynchronously (using gst_clock_id_wait_async() or gst_clock_id_wait_async()). This is used by many GStreamer elements, among them #GstBaseSrc and #GstBaseSink.

#GstTestClock keeps track of these clock notifications. By calling gst_test_clock_wait_for_next_pending_id() or gst_test_clock_wait_for_multiple_pending_ids() a unit tests may wait for the next one or several clock notifications to be requested. Additionally unit tests may release blocked waits in a controlled fashion by calling gst_test_clock_process_next_clock_id(). This way a unit test can control the inaccuracy (jitter) of clock notifications, since the test can decide to release blocked waits when the clock time has advanced exactly to, or past, the requested clock notification time.

There are also interfaces for determining if a notification belongs to a #GstTestClock or not, as well as getting the number of requested clock notifications so far.

N.B.: When a unit test waits for a certain amount of clock notifications to be requested in gst_test_clock_wait_for_next_pending_id() or gst_test_clock_wait_for_multiple_pending_ids() then these functions may block for a long time. If they block forever then the expected clock notifications were never requested from #GstTestClock, and so the assumptions in the code of the unit test are wrong. The unit test case runner in gstcheck is expected to catch these cases either by the default test case timeout or the one set for the unit test by calling tcase_set_timeout().

The sample code below assumes that the element under test will delay a buffer pushed on the source pad by some latency until it arrives on the sink pad. Moreover it is assumed that the element will at some point call gst_clock_id_wait() to synchronously wait for a specific time. The first buffer sent will arrive exactly on time only delayed by the latency. The second buffer will arrive a little late (7ms) due to simulated jitter in the clock notification.

Demonstration of how to work with clock notifications and #GstTestClock

  #include <gst/gst.h>
#include <gst/check/gstcheck.h>
#include <gst/check/gsttestclock.h>

GstClockTime latency;
GstElement *element;
GstPad *srcpad;
GstClock *clock;
GstTestClock *test_clock;
GstBuffer buf;
GstClockID pending_id;
GstClockID processed_id;

latency = 42 * GST_MSECOND;
element = create_element (latency, ...);
srcpad = get_source_pad (element);

clock = gst_test_clock_new ();
test_clock = GST_TEST_CLOCK (clock);
gst_element_set_clock (element, clock);

GST_INFO ("Set time, create and push the first buffer\n");
gst_test_clock_set_time (test_clock, 0);
buf = create_test_buffer (gst_clock_get_time (clock), ...);
gst_assert_cmpint (gst_pad_push (srcpad, buf), ==, GST_FLOW_OK);

GST_INFO ("Block until element is waiting for a clock notification\n");
gst_test_clock_wait_for_next_pending_id (test_clock, &pending_id);
GST_INFO ("Advance to the requested time of the clock notification\n");
gst_test_clock_advance_time (test_clock, latency);
GST_INFO ("Release the next blocking wait and make sure it is the one from element\n");
processed_id = gst_test_clock_process_next_clock_id (test_clock);
g_assert (processed_id == pending_id);
g_assert_cmpint (GST_CLOCK_ENTRY_STATUS (processed_id), ==, GST_CLOCK_OK);
gst_clock_id_unref (pending_id);
gst_clock_id_unref (processed_id);

GST_INFO ("Validate that element produced an output buffer and check its timestamp\n");
g_assert_cmpint (get_number_of_output_buffer (...), ==, 1);
buf = get_buffer_pushed_by_element (element, ...);
g_assert_cmpint (GST_BUFFER_TIMESTAMP (buf), ==, latency);
gst_buffer_unref (buf);
GST_INFO ("Check that element does not wait for any clock notification\n");
g_assert (!gst_test_clock_peek_next_pending_id (test_clock, NULL));

GST_INFO ("Set time, create and push the second buffer\n");
gst_test_clock_advance_time (test_clock, 10 * GST_SECOND);
buf = create_test_buffer (gst_clock_get_time (clock), ...);
gst_assert_cmpint (gst_pad_push (srcpad, buf), ==, GST_FLOW_OK);

GST_INFO ("Block until element is waiting for a new clock notification\n");
(gst_test_clock_wait_for_next_pending_id (test_clock, &pending_id);
GST_INFO ("Advance past 7ms beyond the requested time of the clock notification\n");
gst_test_clock_advance_time (test_clock, latency + 7 * GST_MSECOND);
GST_INFO ("Release the next blocking wait and make sure it is the one from element\n");
processed_id = gst_test_clock_process_next_clock_id (test_clock);
g_assert (processed_id == pending_id);
g_assert_cmpint (GST_CLOCK_ENTRY_STATUS (processed_id), ==, GST_CLOCK_OK);
gst_clock_id_unref (pending_id);
gst_clock_id_unref (processed_id);

GST_INFO ("Validate that element produced an output buffer and check its timestamp\n");
g_assert_cmpint (get_number_of_output_buffer (...), ==, 1);
buf = get_buffer_pushed_by_element (element, ...);
g_assert_cmpint (GST_BUFFER_TIMESTAMP (buf), ==,
10 * GST_SECOND + latency + 7 * GST_MSECOND);
gst_buffer_unref (buf);
GST_INFO ("Check that element does not wait for any clock notification\n");
g_assert (!gst_test_clock_peek_next_pending_id (test_clock, NULL));
...

Since #GstTestClock is only supposed to be used in unit tests it calls g_assert(), g_assert_cmpint() or g_assert_cmpuint() to validate all function arguments. This will highlight any issues with the unit test code itself.

Hierarchy

Index

Constructors

Properties

Methods

Constructors

Properties

clock_type: Gst.ClockType
flags: number

flags for this object

field
g_type_instance: TypeInstance
name: string

The name of the object

field
object: any

the parent structure

parent: Gst.Clock

this object's parent, weak ref

start_time: number

When a #GstTestClock is constructed it will have a certain start time set. If the clock was created using gst_test_clock_new_with_start_time() then this property contains the value of the start_time argument. If gst_test_clock_new() was called the clock started at time zero, and thus this property contains the value 0.

timeout: number
window_size: number
window_threshold: number
$gtype: GType<TestClock>
name: string

Methods

  • Attach the #GstControlBinding to the object. If there already was a #GstControlBinding for this property it will be replaced.

    The object's reference count will be incremented, and any floating reference will be removed (see gst_object_ref_sink())

    Parameters

    Returns boolean

  • add_observation(slave: number, master: number): [boolean, number]
  • The time master of the master clock and the time slave of the slave clock are added to the list of observations. If enough observations are available, a linear regression algorithm is run on the observations and clock is recalibrated.

    If this functions returns %TRUE, r_squared will contain the correlation coefficient of the interpolation. A value of 1.0 means a perfect regression was performed. This value can be used to control the sampling frequency of the master and slave clocks.

    Parameters

    • slave: number

      a time on the slave

    • master: number

      a time on the master

    Returns [boolean, number]

  • add_observation_unapplied(slave: number, master: number): [boolean, number, number, number, number, number]
  • Add a clock observation to the internal slaving algorithm the same as gst_clock_add_observation(), and return the result of the master clock estimation, without updating the internal calibration.

    The caller can then take the results and call gst_clock_set_calibration() with the values, or some modified version of them.

    Parameters

    • slave: number

      a time on the slave

    • master: number

      a time on the master

    Returns [boolean, number, number, number, number, number]

  • adjust_unlocked(internal: number): number
  • Converts the given internal clock time to the external time, adjusting for the rate and reference time set with gst_clock_set_calibration() and making sure that the returned time is increasing. This function should be called with the clock's OBJECT_LOCK held and is mainly used by clock subclasses.

    This function is the reverse of gst_clock_unadjust_unlocked().

    Parameters

    • internal: number

      a clock time

    Returns number

  • adjust_with_calibration(internal_target: number, cinternal: number, cexternal: number, cnum: number, cdenom: number): number
  • Converts the given internal_target clock time to the external time, using the passed calibration parameters. This function performs the same calculation as gst_clock_adjust_unlocked() when called using the current calibration parameters, but doesn't ensure a monotonically increasing result as gst_clock_adjust_unlocked() does.

    Note: The clock parameter is unused and can be NULL

    Parameters

    • internal_target: number

      a clock time

    • cinternal: number

      a reference internal time

    • cexternal: number

      a reference external time

    • cnum: number

      the numerator of the rate of the clock relative to its internal time

    • cdenom: number

      the denominator of the rate of the clock

    Returns number

  • advance_time(delta: number): void
  • Advances the time of the test_clock by the amount given by delta. The time of test_clock is monotonically increasing, therefore providing a delta which is negative or zero is a programming error.

    MT safe.

    Parameters

    • delta: number

      a positive #GstClockTimeDiff to be added to the time of the clock

    Returns void

  • Creates a binding between source_property on source and target_property on target.

    Whenever the source_property is changed the target_property is updated using the same value. For instance:

      g_object_bind_property (action, "active", widget, "sensitive", 0);
    

    Will result in the "sensitive" property of the widget #GObject instance to be updated with the same value of the "active" property of the action #GObject instance.

    If flags contains %G_BINDING_BIDIRECTIONAL then the binding will be mutual: if target_property on target changes then the source_property on source will be updated as well.

    The binding will automatically be removed when either the source or the target instances are finalized. To remove the binding without affecting the source and the target you can just call g_object_unref() on the returned #GBinding instance.

    Removing the binding by calling g_object_unref() on it must only be done if the binding, source and target are only used from a single thread and it is clear that both source and target outlive the binding. Especially it is not safe to rely on this if the binding, source or target can be finalized from different threads. Keep another reference to the binding and use g_binding_unbind() instead to be on the safe side.

    A #GObject can have multiple bindings.

    Parameters

    • source_property: string

      the property on source to bind

    • target: GObject.Object

      the target #GObject

    • target_property: string

      the property on target to bind

    • flags: BindingFlags

      flags to pass to #GBinding

    Returns Binding

  • Creates a binding between source_property on source and target_property on target, allowing you to set the transformation functions to be used by the binding.

    This function is the language bindings friendly version of g_object_bind_property_full(), using #GClosures instead of function pointers.

    Parameters

    • source_property: string

      the property on source to bind

    • target: GObject.Object

      the target #GObject

    • target_property: string

      the property on target to bind

    • flags: BindingFlags

      flags to pass to #GBinding

    • transform_to: TClosure<any, any>

      a #GClosure wrapping the transformation function from the source to the target, or %NULL to use the default

    • transform_from: TClosure<any, any>

      a #GClosure wrapping the transformation function from the target to the source, or %NULL to use the default

    Returns Binding

  • connect(sigName: "notify::clock-type", callback: (($obj: TestClock, pspec: ParamSpec) => void)): number
  • connect(sigName: "notify::start-time", callback: (($obj: TestClock, pspec: ParamSpec) => void)): number
  • connect(sigName: "notify::timeout", callback: (($obj: TestClock, pspec: ParamSpec) => void)): number
  • connect(sigName: "notify::window-size", callback: (($obj: TestClock, pspec: ParamSpec) => void)): number
  • connect(sigName: "notify::window-threshold", callback: (($obj: TestClock, pspec: ParamSpec) => void)): number
  • connect(sigName: string, callback: ((...args: any[]) => void)): number
  • connect_after(sigName: "notify::clock-type", callback: (($obj: TestClock, pspec: ParamSpec) => void)): number
  • connect_after(sigName: "notify::start-time", callback: (($obj: TestClock, pspec: ParamSpec) => void)): number
  • connect_after(sigName: "notify::timeout", callback: (($obj: TestClock, pspec: ParamSpec) => void)): number
  • connect_after(sigName: "notify::window-size", callback: (($obj: TestClock, pspec: ParamSpec) => void)): number
  • connect_after(sigName: "notify::window-threshold", callback: (($obj: TestClock, pspec: ParamSpec) => void)): number
  • connect_after(sigName: string, callback: ((...args: any[]) => void)): number
  • crank(): boolean
  • A "crank" consists of three steps: 1: Wait for a #GstClockID to be registered with the #GstTestClock. 2: Advance the #GstTestClock to the time the #GstClockID is waiting, unless the clock time is already passed the clock id (Since: 1.18). 3: Release the #GstClockID wait. A "crank" can be though of as the notion of manually driving the clock forward to its next logical step.

    Returns boolean

  • default_error(error: GLib.Error, debug: string): void
  • A default error function that uses g_printerr() to display the error message and the optional debug string..

    The default handler will simply print the error string using g_print.

    Parameters

    • error: GLib.Error

      the GError.

    • debug: string

      an additional debug information string, or %NULL

    Returns void

  • disconnect(id: number): void
  • emit(sigName: "notify::clock-type", ...args: any[]): void
  • emit(sigName: "notify::start-time", ...args: any[]): void
  • emit(sigName: "notify::timeout", ...args: any[]): void
  • emit(sigName: "notify::window-size", ...args: any[]): void
  • emit(sigName: "notify::window-threshold", ...args: any[]): void
  • emit(sigName: string, ...args: any[]): void
  • force_floating(): void
  • This function is intended for #GObject implementations to re-enforce a [floating][floating-ref] object reference. Doing this is seldom required: all #GInitiallyUnowneds are created with a floating reference which usually just needs to be sunken by calling g_object_ref_sink().

    Returns void

  • freeze_notify(): void
  • Increases the freeze count on object. If the freeze count is non-zero, the emission of "notify" signals on object is stopped. The signals are queued until the freeze count is decreased to zero. Duplicate notifications are squashed so that at most one #GObject::notify signal is emitted for each property modified while the object is frozen.

    This is necessary for accessors that modify multiple properties to prevent premature notification while the object is still being modified.

    Returns void

  • get_calibration(): [number, number, number, number]
  • Gets the internal rate and reference time of clock. See gst_clock_set_calibration() for more information.

    internal, external, rate_num, and rate_denom can be left %NULL if the caller is not interested in the values.

    Returns [number, number, number, number]

  • get_control_rate(): number
  • Obtain the control-rate for this object. Audio processing #GstElement objects will use this rate to sub-divide their processing loop and call gst_object_sync_values() in between. The length of the processing segment should be up to control-rate nanoseconds.

    If the object is not under property control, this will return %GST_CLOCK_TIME_NONE. This allows the element to avoid the sub-dividing.

    The control-rate is not expected to change if the element is in %GST_STATE_PAUSED or %GST_STATE_PLAYING.

    Returns number

  • get_data(key?: string): object
  • Gets a named field from the objects table of associations (see g_object_set_data()).

    Parameters

    • Optional key: string

      name of the key for that association

    Returns object

  • get_g_value_array(property_name: string, timestamp?: number, interval?: number, values?: any[]): boolean
  • Gets a number of #GValues for the given controlled property starting at the requested time. The array values need to hold enough space for n_values of #GValue.

    This function is useful if one wants to e.g. draw a graph of the control curve or apply a control curve sample by sample.

    Parameters

    • property_name: string

      the name of the property to get

    • Optional timestamp: number

      the time that should be processed

    • Optional interval: number

      the time spacing between subsequent values

    • Optional values: any[]

      array to put control-values in

    Returns boolean

  • get_internal_time(): number
  • get_name(): string
  • Returns a copy of the name of object. Caller should g_free() the return value after usage. For a nameless object, this returns %NULL, which you can safely g_free() as well.

    Free-function: g_free

    Returns string

  • get_next_entry_time(): number
  • get_path_string(): string
  • get_property(property_name?: string, value?: any): void
  • Gets a property of an object.

    The value can be:

    • an empty #GValue initialized by %G_VALUE_INIT, which will be automatically initialized with the expected type of the property (since GLib 2.60)
    • a #GValue initialized with the expected type of the property
    • a #GValue initialized with a type to which the expected type of the property can be transformed

    In general, a copy is made of the property contents and the caller is responsible for freeing the memory by calling g_value_unset().

    Note that g_object_get_property() is really intended for language bindings, g_object_get() is much more convenient for C programming.

    Parameters

    • Optional property_name: string

      the name of the property to get

    • Optional value: any

      return location for the property value

    Returns void

  • get_qdata(quark: number): object
  • get_resolution(): number
  • get_time(): number
  • Gets the current time of the given clock. The time is always monotonically increasing and adjusted according to the current offset and rate.

    Returns number

  • get_timeout(): number
  • get_value(property_name: string, timestamp?: number): any
  • Gets the value for the given controlled property at the requested time.

    Parameters

    • property_name: string

      the name of the property to get

    • Optional timestamp: number

      the time the control-change should be read from

    Returns any

  • getv(names: string[], values: any[]): void
  • Gets n_properties properties for an object. Obtained properties will be set to values. All properties must be valid. Warnings will be emitted and undefined behaviour may result if invalid properties are passed in.

    Parameters

    • names: string[]

      the names of each property to get

    • values: any[]

      the values of each property to get

    Returns void

  • has_active_control_bindings(): boolean
  • Check if object has an ancestor ancestor somewhere up in the hierarchy. One can e.g. check if a #GstElement is inside a #GstPipeline.

    Parameters

    • ancestor: Gst.Object

      a #GstObject to check as ancestor

    Returns boolean

  • has_as_ancestor(ancestor: Gst.Object): boolean
  • Check if object has an ancestor ancestor somewhere up in the hierarchy. One can e.g. check if a #GstElement is inside a #GstPipeline.

    Parameters

    • ancestor: Gst.Object

      a #GstObject to check as ancestor

    Returns boolean

  • has_id(id: object): boolean
  • Checks whether test_clock was requested to provide the clock notification given by id.

    MT safe.

    Parameters

    • id: object

      a #GstClockID clock notification

    Returns boolean

  • is_floating(): boolean
  • is_synced(): boolean
  • new_periodic_id(start_time: number, interval: number): object
  • Gets an ID from clock to trigger a periodic notification. The periodic notifications will start at time start_time and will then be fired with the given interval.

    Parameters

    • start_time: number

      the requested start time

    • interval: number

      the requested interval

    Returns object

  • new_single_shot_id(time: number): object
  • notify(property_name: string): void
  • Emits a "notify" signal for the property property_name on object.

    When possible, eg. when signaling a property change from within the class that registered the property, you should use g_object_notify_by_pspec() instead.

    Note that emission of the notify signal may be blocked with g_object_freeze_notify(). In this case, the signal emissions are queued and will be emitted (in reverse order) when g_object_thaw_notify() is called.

    Parameters

    • property_name: string

      the name of a property installed on the class of object.

    Returns void

  • Emits a "notify" signal for the property specified by pspec on object.

    This function omits the property name lookup, hence it is faster than g_object_notify().

    One way to avoid using g_object_notify() from within the class that registered the properties, and using g_object_notify_by_pspec() instead, is to store the GParamSpec used with g_object_class_install_property() inside a static array, e.g.:

      enum
    {
    PROP_0,
    PROP_FOO,
    PROP_LAST
    };

    static GParamSpec *properties[PROP_LAST];

    static void
    my_object_class_init (MyObjectClass *klass)
    {
    properties[PROP_FOO] = g_param_spec_int ("foo", "Foo", "The foo",
    0, 100,
    50,
    G_PARAM_READWRITE);
    g_object_class_install_property (gobject_class,
    PROP_FOO,
    properties[PROP_FOO]);
    }

    and then notify a change on the "foo" property with:

      g_object_notify_by_pspec (self, properties[PROP_FOO]);
    

    Parameters

    • pspec: ParamSpec

      the #GParamSpec of a property installed on the class of object.

    Returns void

  • peek_id_count(): number
  • Determine the number of pending clock notifications that have been requested from the test_clock.

    MT safe.

    Returns number

  • peek_next_pending_id(): [boolean, object]
  • Determines if the pending_id is the next clock notification scheduled to be triggered given the current time of the test_clock.

    MT safe.

    Returns [boolean, object]

  • periodic_id_reinit(id: object, start_time: number, interval: number): boolean
  • Reinitializes the provided periodic id to the provided start time and interval. Does not modify the reference count.

    Parameters

    • id: object

      a #GstClockID

    • start_time: number

      the requested start time

    • interval: number

      the requested interval

    Returns boolean

  • process_id(pending_id: object): boolean
  • process_id_list(pending_list: object[]): number
  • Processes and releases the pending IDs in the list.

    MT safe.

    Parameters

    • pending_list: object[]

      List of pending #GstClockIDs

    Returns number

  • process_next_clock_id(): object
  • ref(...args: any[]): any
  • Increments the reference count on object. This function does not take the lock on object because it relies on atomic refcounting.

    This object returns the input parameter to ease writing constructs like : result = gst_object_ref (object->parent);

    Parameters

    • Rest ...args: any[]

    Returns any

  • Increase the reference count of object, and possibly remove the [floating][floating-ref] reference, if object has a floating reference.

    In other words, if the object is floating, then this call "assumes ownership" of the floating reference, converting it to a normal reference by clearing the floating flag while leaving the reference count unchanged. If the object is not floating, then this call adds a new normal reference increasing the reference count by one.

    Since GLib 2.56, the type of object will be propagated to the return type under the same conditions as for g_object_ref().

    Returns GObject.Object

  • run_dispose(): void
  • Releases all references to other objects. This can be used to break reference cycles.

    This function should only be called from object system implementations.

    Returns void

  • set_calibration(internal: number, external: number, rate_num: number, rate_denom: number): void
  • Adjusts the rate and time of clock. A rate of 1/1 is the normal speed of the clock. Values bigger than 1/1 make the clock go faster.

    internal and external are calibration parameters that arrange that gst_clock_get_time() should have been external at internal time internal. This internal time should not be in the future; that is, it should be less than the value of gst_clock_get_internal_time() when this function is called.

    Subsequent calls to gst_clock_get_time() will return clock times computed as follows:

      time = (internal_time - internal) * rate_num / rate_denom + external
    

    This formula is implemented in gst_clock_adjust_unlocked(). Of course, it tries to do the integer arithmetic as precisely as possible.

    Note that gst_clock_get_time() always returns increasing values so when you move the clock backwards, gst_clock_get_time() will report the previous value until the clock catches up.

    Parameters

    • internal: number

      a reference internal time

    • external: number

      a reference external time

    • rate_num: number

      the numerator of the rate of the clock relative to its internal time

    • rate_denom: number

      the denominator of the rate of the clock

    Returns void

  • set_control_binding_disabled(property_name: string, disabled: boolean): void
  • This function is used to disable the control bindings on a property for some time, i.e. gst_object_sync_values() will do nothing for the property.

    Parameters

    • property_name: string

      property to disable

    • disabled: boolean

      boolean that specifies whether to disable the controller or not.

    Returns void

  • set_control_bindings_disabled(disabled: boolean): void
  • This function is used to disable all controlled properties of the object for some time, i.e. gst_object_sync_values() will do nothing.

    Parameters

    • disabled: boolean

      boolean that specifies whether to disable the controller or not.

    Returns void

  • set_control_rate(control_rate: number): void
  • Change the control-rate for this object. Audio processing #GstElement objects will use this rate to sub-divide their processing loop and call gst_object_sync_values() in between. The length of the processing segment should be up to control-rate nanoseconds.

    The control-rate should not change if the element is in %GST_STATE_PAUSED or %GST_STATE_PLAYING.

    Parameters

    • control_rate: number

      the new control-rate in nanoseconds.

    Returns void

  • set_data(key: string, data?: object): void
  • Each object carries around a table of associations from strings to pointers. This function lets you set an association.

    If the object already had an association with that name, the old association will be destroyed.

    Internally, the key is converted to a #GQuark using g_quark_from_string(). This means a copy of key is kept permanently (even after object has been finalized) — so it is recommended to only use a small, bounded set of values for key in your program, to avoid the #GQuark storage growing unbounded.

    Parameters

    • key: string

      name of the key

    • Optional data: object

      data to associate with that key

    Returns void

  • Sets master as the master clock for clock. clock will be automatically calibrated so that gst_clock_get_time() reports the same time as the master clock.

    A clock provider that slaves its clock to a master can get the current calibration values with gst_clock_get_calibration().

    master can be %NULL in which case clock will not be slaved anymore. It will however keep reporting its time adjusted with the last configured rate and time offsets.

    Parameters

    Returns boolean

  • set_name(name: string): boolean
  • Sets the name of object, or gives object a guaranteed unique name (if name is %NULL). This function makes a copy of the provided name, so the caller retains ownership of the name it sent.

    Parameters

    • name: string

      new name of object

    Returns boolean

  • Sets the parent of object to parent. The object's reference count will be incremented, and any floating reference will be removed (see gst_object_ref_sink()).

    Parameters

    Returns boolean

  • set_property(property_name: string, value?: any): void
  • set_resolution(resolution: number): number
  • Sets the accuracy of the clock. Some clocks have the possibility to operate with different accuracy at the expense of more resource usage. There is normally no need to change the default resolution of a clock. The resolution of a clock can only be changed if the clock has the #GST_CLOCK_FLAG_CAN_SET_RESOLUTION flag set.

    Parameters

    • resolution: number

      The resolution to set

    Returns number

  • set_synced(synced: boolean): void
  • Sets clock to synced and emits the #GstClock::synced signal, and wakes up any thread waiting in gst_clock_wait_for_sync().

    This function must only be called if %GST_CLOCK_FLAG_NEEDS_STARTUP_SYNC is set on the clock, and is intended to be called by subclasses only.

    Parameters

    • synced: boolean

      if the clock is synced

    Returns void

  • set_time(new_time: number): void
  • Sets the time of test_clock to the time given by new_time. The time of test_clock is monotonically increasing, therefore providing a new_time which is earlier or equal to the time of the clock as given by gst_clock_get_time() is a programming error.

    MT safe.

    Parameters

    • new_time: number

      a #GstClockTime later than that returned by gst_clock_get_time()

    Returns void

  • set_timeout(timeout: number): void
  • single_shot_id_reinit(id: object, time: number): boolean
  • steal_data(key?: string): object
  • Remove a specified datum from the object's data associations, without invoking the association's destroy handler.

    Parameters

    • Optional key: string

      name of the key

    Returns object

  • steal_qdata(quark: number): object
  • This function gets back user data pointers stored via g_object_set_qdata() and removes the data from object without invoking its destroy() function (if any was set). Usually, calling this function is only required to update user data pointers with a destroy notifier, for example:

    void
    object_add_to_user_list (GObject *object,
    const gchar *new_string)
    {
    // the quark, naming the object data
    GQuark quark_string_list = g_quark_from_static_string ("my-string-list");
    // retrieve the old string list
    GList *list = g_object_steal_qdata (object, quark_string_list);

    // prepend new string
    list = g_list_prepend (list, g_strdup (new_string));
    // this changed 'list', so we need to set it again
    g_object_set_qdata_full (object, quark_string_list, list, free_string_list);
    }
    static void
    free_string_list (gpointer data)
    {
    GList *node, *list = data;

    for (node = list; node; node = node->next)
    g_free (node->data);
    g_list_free (list);
    }

    Using g_object_get_qdata() in the above example, instead of g_object_steal_qdata() would have left the destroy function set, and thus the partial string list would have been freed upon g_object_set_qdata_full().

    Parameters

    • quark: number

      A #GQuark, naming the user data pointer

    Returns object

  • suggest_next_sync(): number
  • sync_values(timestamp: number): boolean
  • Sets the properties of the object, according to the #GstControlSources that (maybe) handle them and for the given timestamp.

    If this function fails, it is most likely the application developers fault. Most probably the control sources are not setup correctly.

    Parameters

    • timestamp: number

      the time that should be processed

    Returns boolean

  • thaw_notify(): void
  • Reverts the effect of a previous call to g_object_freeze_notify(). The freeze count is decreased on object and when it reaches zero, queued "notify" signals are emitted.

    Duplicate notifications for each property are squashed so that at most one #GObject::notify signal is emitted for each property, in the reverse order in which they have been queued.

    It is an error to call this function when the freeze count is zero.

    Returns void

  • timed_wait_for_multiple_pending_ids(count: number, timeout_ms: number): [boolean, object[]]
  • Blocks until at least count clock notifications have been requested from test_clock, or the timeout expires.

    MT safe.

    Parameters

    • count: number

      the number of pending clock notifications to wait for

    • timeout_ms: number

      the timeout in milliseconds

    Returns [boolean, object[]]

  • unadjust_unlocked(external: number): number
  • Converts the given external clock time to the internal time of clock, using the rate and reference time set with gst_clock_set_calibration(). This function should be called with the clock's OBJECT_LOCK held and is mainly used by clock subclasses.

    This function is the reverse of gst_clock_adjust_unlocked().

    Parameters

    • external: number

      an external clock time

    Returns number

  • unadjust_with_calibration(external_target: number, cinternal: number, cexternal: number, cnum: number, cdenom: number): number
  • Converts the given external_target clock time to the internal time, using the passed calibration parameters. This function performs the same calculation as gst_clock_unadjust_unlocked() when called using the current calibration parameters.

    Note: The clock parameter is unused and can be NULL

    Parameters

    • external_target: number

      a clock time

    • cinternal: number

      a reference internal time

    • cexternal: number

      a reference external time

    • cnum: number

      the numerator of the rate of the clock relative to its internal time

    • cdenom: number

      the denominator of the rate of the clock

    Returns number

  • unparent(): void
  • Clear the parent of object, removing the associated reference. This function decreases the refcount of object.

    MT safe. Grabs and releases object's lock.

    Returns void

  • unref(): void
  • Decrements the reference count on object. If reference count hits zero, destroy object. This function does not take the lock on object as it relies on atomic refcounting.

    The unref method should never be called with the LOCK held since this might deadlock the dispose function.

    Returns void

  • vfunc_change_resolution(old_resolution: number, new_resolution: number): number
  • vfunc_constructed(): void
  • vfunc_dispatch_properties_changed(n_pspecs: number, pspecs: ParamSpec): void
  • vfunc_dispose(): void
  • vfunc_finalize(): void
  • vfunc_get_internal_time(): number
  • vfunc_get_property(property_id: number, value?: any, pspec?: ParamSpec): void
  • vfunc_get_resolution(): number
  • Emits a "notify" signal for the property property_name on object.

    When possible, eg. when signaling a property change from within the class that registered the property, you should use g_object_notify_by_pspec() instead.

    Note that emission of the notify signal may be blocked with g_object_freeze_notify(). In this case, the signal emissions are queued and will be emitted (in reverse order) when g_object_thaw_notify() is called.

    virtual

    Parameters

    Returns void

  • vfunc_set_property(property_id: number, value?: any, pspec?: ParamSpec): void
  • wait_for_multiple_pending_ids(count: number): object[]
  • Blocks until at least count clock notifications have been requested from test_clock. There is no timeout for this wait, see the main description of #GstTestClock.

    MT safe.

    Parameters

    • count: number

      the number of pending clock notifications to wait for

    Returns object[]

  • wait_for_next_pending_id(): object
  • Waits until a clock notification is requested from test_clock. There is no timeout for this wait, see the main description of #GstTestClock. A reference to the pending clock notification is stored in pending_id.

    MT safe.

    Returns object

  • wait_for_pending_id_count(count: number): void
  • Blocks until at least count clock notifications have been requested from test_clock. There is no timeout for this wait, see the main description of #GstTestClock.

    Parameters

    • count: number

      the number of pending clock notifications to wait for

    Returns void

  • wait_for_sync(timeout: number): boolean
  • Waits until clock is synced for reporting the current time. If timeout is %GST_CLOCK_TIME_NONE it will wait forever, otherwise it will time out after timeout nanoseconds.

    For asynchronous waiting, the #GstClock::synced signal can be used.

    This returns immediately with %TRUE if %GST_CLOCK_FLAG_NEEDS_STARTUP_SYNC is not set on the clock, or if the clock is already synced.

    Parameters

    • timeout: number

      timeout for waiting or %GST_CLOCK_TIME_NONE

    Returns boolean

  • watch_closure(closure: TClosure<any, any>): void
  • This function essentially limits the life time of the closure to the life time of the object. That is, when the object is finalized, the closure is invalidated by calling g_closure_invalidate() on it, in order to prevent invocations of the closure with a finalized (nonexisting) object. Also, g_object_ref() and g_object_unref() are added as marshal guards to the closure, to ensure that an extra reference count is held on object during invocation of the closure. Usually, this function will be called on closures that use this object as closure data.

    Parameters

    • closure: TClosure<any, any>

      #GClosure to watch

    Returns void

  • check_uniqueness(list: Gst.Object[], name: string): boolean
  • Checks to see if there is any object named name in list. This function does not do any locking of any kind. You might want to protect the provided list with the lock of the owner of the list. This function will lock each #GstObject in the list to compare the name, so be careful when passing a list with a locked object.

    Parameters

    • list: Gst.Object[]

      a list of #GstObject to check through

    • name: string

      the name to search for

    Returns boolean

  • compat_control(what: number, data: object): number
  • A default deep_notify signal callback for an object. The user data should contain a pointer to an array of strings that should be excluded from the notify. The default handler will print the new value of the property using g_print.

    MT safe. This function grabs and releases object's LOCK for getting its path string.

    Parameters

    • object: GObject.Object

      the #GObject that signalled the notify.

    • orig: Gst.Object

      a #GstObject that initiated the notify.

    • pspec: ParamSpec

      a #GParamSpec of the property.

    • excluded_props: string[]

      a set of user-specified properties to exclude or %NULL to show all changes.

    Returns void

  • id_compare_func(id1: object, id2: object): number
  • Compares the two #GstClockID instances. This function can be used as a GCompareFunc when sorting ids.

    Parameters

    • id1: object

      A #GstClockID

    • id2: object

      A #GstClockID to compare with

    Returns number

  • id_get_time(id: object): number
  • id_list_get_latest_time(pending_list: object[]): number
  • Finds the latest time inside the list.

    MT safe.

    Parameters

    • pending_list: object[]

      List of of pending #GstClockIDs

    Returns number

  • id_ref(id: object): object
  • id_unref(id: object): void
  • id_unschedule(id: object): void
  • Cancels an outstanding request with id. This can either be an outstanding async notification or a pending sync notification. After this call, id cannot be used anymore to receive sync or async notifications, you need to create a new #GstClockID.

    Parameters

    • id: object

      The id to unschedule

    Returns void

  • id_uses_clock(id: object, clock: Gst.Clock): boolean
  • This function returns whether id uses clock as the underlying clock. clock can be NULL, in which case the return value indicates whether the underlying clock has been freed. If this is the case, the id is no longer usable and should be freed.

    Parameters

    • id: object

      a #GstClockID to check

    • clock: Gst.Clock

      a #GstClock to compare against

    Returns boolean

  • Performs a blocking wait on id. id should have been created with gst_clock_new_single_shot_id() or gst_clock_new_periodic_id() and should not have been unscheduled with a call to gst_clock_id_unschedule().

    If the jitter argument is not %NULL and this function returns #GST_CLOCK_OK or #GST_CLOCK_EARLY, it will contain the difference against the clock and the time of id when this method was called. Positive values indicate how late id was relative to the clock (in which case this function will return #GST_CLOCK_EARLY). Negative values indicate how much time was spent waiting on the clock before this function returned.

    Parameters

    • id: object

      The #GstClockID to wait on

    Returns [Gst.ClockReturn, number]

  • Registers a callback on the given #GstClockID id with the given function and user_data. When passing a #GstClockID with an invalid time to this function, the callback will be called immediately with a time set to %GST_CLOCK_TIME_NONE. The callback will be called when the time of id has been reached.

    The callback func can be invoked from any thread, either provided by the core or from a streaming thread. The application should be prepared for this.

    Parameters

    • id: object

      a #GstClockID to wait on

    • func: Gst.ClockCallback

      The callback function

    Returns Gst.ClockReturn

  • Find the #GParamSpec with the given name for an interface. Generally, the interface vtable passed in as g_iface will be the default vtable from g_type_default_interface_ref(), or, if you know the interface has already been loaded, g_type_default_interface_peek().

    Parameters

    • g_iface: TypeInterface

      any interface vtable for the interface, or the default vtable for the interface

    • property_name: string

      name of a property to look up.

    Returns ParamSpec

  • Add a property to an interface; this is only useful for interfaces that are added to GObject-derived types. Adding a property to an interface forces all objects classes with that interface to have a compatible property. The compatible property could be a newly created #GParamSpec, but normally g_object_class_override_property() will be used so that the object class only needs to provide an implementation and inherits the property description, default value, bounds, and so forth from the interface property.

    This function is meant to be called from the interface's default vtable initialization function (the class_init member of #GTypeInfo.) It must not be called after after class_init has been called for any object types implementing this interface.

    If pspec is a floating reference, it will be consumed.

    Parameters

    • g_iface: TypeInterface

      any interface vtable for the interface, or the default vtable for the interface.

    • pspec: ParamSpec

      the #GParamSpec for the new property

    Returns void

  • Lists the properties of an interface.Generally, the interface vtable passed in as g_iface will be the default vtable from g_type_default_interface_ref(), or, if you know the interface has already been loaded, g_type_default_interface_peek().

    Parameters

    • g_iface: TypeInterface

      any interface vtable for the interface, or the default vtable for the interface

    Returns ParamSpec[]

  • new_with_start_time(start_time: number): TestClock
  • Creates a new test clock with its time set to the specified time.

    MT safe.

    Parameters

    • start_time: number

      a #GstClockTime set to the desired start time of the clock.

    Returns TestClock

  • Creates a new instance of a #GObject subtype and sets its properties.

    Construction parameters (see %G_PARAM_CONSTRUCT, %G_PARAM_CONSTRUCT_ONLY) which are not explicitly specified are set to their default values.

    Parameters

    • object_type: GType<unknown>

      the type id of the #GObject subtype to instantiate

    • parameters: GObject.Parameter[]

      an array of #GParameter

    Returns GObject.Object

  • Atomically modifies a pointer to point to a new object. The reference count of oldobj is decreased and the reference count of newobj is increased.

    Either newobj and the value pointed to by oldobj may be %NULL.

    Parameters

    • oldobj: Gst.Object

      pointer to a place of a #GstObject to replace

    • newobj: Gst.Object

      a new #GstObject

    Returns [boolean, Gst.Object]

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