boolean indicating that the ringbuffer is acquired
used to signal start/stop/pause/resume actions
pointer to memory holding one segment of silence samples
flags for this object
data in the ringbuffer
The name of the object
boolean indicating that the ringbuffer is open
this object's parent, weak ref
number of samples in one segment
segment corresponding to segment 0 (unused)
readpointer in the ringbuffer
size of data in the ringbuffer
format and layout of the ringbuffer data
state of the buffer
is a reader or writer waiting for a free segment
Allocate the resources for the ringbuffer. This function fills in the data pointer of the ring buffer with a valid #GstBuffer to which samples can be written.
the specs of the buffer
Activate buf
to start or stop pulling data.
MT safe.
the new mode
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())
the #GstControlBinding that should be used
Subclasses should call this function to notify the fact that
advance
segments are now processed by the device.
MT safe.
the number of segments written
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.
the property on source
to bind
the target #GObject
the property on target
to bind
flags to pass to #GBinding
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.
the property on source
to bind
the target #GObject
the property on target
to bind
flags to pass to #GBinding
a #GClosure wrapping the transformation function from the source
to the target,
or %NULL to use the default
a #GClosure wrapping the transformation function from the target
to the source,
or %NULL to use the default
Clear the given segment of the buffer with silence samples. This function is used by subclasses.
MT safe.
the segment to clear
Clear all samples from the ringbuffer.
MT safe.
Close the audio device associated with the ring buffer. The ring buffer should already have been released via gst_audio_ring_buffer_release().
Commit in_samples
samples pointed to by data
to the ringbuffer buf
.
in_samples
and out_samples
define the rate conversion to perform on the
samples in data
. For negative rates, out_samples
must be negative and
in_samples
positive.
When out_samples
is positive, the first sample will be written at position sample
in the ringbuffer. When out_samples
is negative, the last sample will be written to
sample
in reverse order.
out_samples
does not need to be a multiple of the segment size of the ringbuffer
although it is recommended for optimal performance.
accum
will hold a temporary accumulator used in rate conversion and should be
set to 0 when this function is first called. In case the commit operation is
interrupted, one can resume the processing by passing the previously returned
accum
value back to this function.
MT safe.
the sample position of the data
the data to commit
the number of samples to write to the ringbuffer
accumulator for rate conversion.
Get the number of samples queued in the audio device. This is usually less than the segment size but can be bigger when the implementation uses another internal buffer between the audio device.
For playback ringbuffers this is the amount of samples transferred from the ringbuffer to the device but still not played.
For capture ringbuffers this is the amount of samples in the device that are not yet transferred to the ringbuffer.
Checks the status of the device associated with the ring buffer.
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().
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.
Gets the corresponding #GstControlBinding for the property. This should be unreferenced again after use.
name of the property
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.
Gets a named field from the objects table of associations (see g_object_set_data()).
name of the key for that association
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.
the name of the property to get
the time that should be processed
the time spacing between subsequent values
array to put control-values in
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
Generates a string describing the path of object
in
the object hierarchy. Only useful (or used) for debugging.
Free-function: g_free
Gets a property of an object.
The value
can be:
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.
the name of the property to get
return location for the property value
This function gets back user data pointers stored via g_object_set_qdata().
A #GQuark, naming the user data pointer
Gets the value for the given controlled property at the requested time.
the name of the property to get
the time the control-change should be read from
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.
the names of each property to get
the values of each property to get
Check if the object
has active controlled properties.
Check if the ringbuffer is acquired and ready to use.
Check if buf
is activated.
MT safe.
Checks whether object
has a [floating][floating-ref] reference.
Check if buf
is flushing.
MT safe.
Tell the ringbuffer that it is allowed to start playback when the ringbuffer is filled with samples.
MT safe.
the new value
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.
the name of a property installed on the class of object
.
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]);
the #GParamSpec of a property installed on the class of object
.
Open the audio device associated with the ring buffer. Does not perform any setup on the device. You must open the device before acquiring the ring buffer.
Pause processing samples from the ringbuffer.
Returns a pointer to memory where the data from segment segment
can be found. This function is mostly used by subclasses.
Read len
samples from the ringbuffer into the memory pointed
to by data
.
The first sample should be read from position sample
in
the ringbuffer.
len
should not be a multiple of the segment size of the ringbuffer
although it is recommended.
timestamp
will return the timestamp associated with the data returned.
the sample position of the data
where the data should be read
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);
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().
Free the resources of the ringbuffer.
Removes the corresponding #GstControlBinding. If it was the last ref of the binding, it will be disposed.
the binding
Releases all references to other objects. This can be used to break reference cycles.
This function should only be called from object system implementations.
Get the number of samples that were processed by the ringbuffer since it was last started. This does not include the number of samples not yet processed (see gst_audio_ring_buffer_delay()).
Sets the given callback function on the buffer. This function will be called every time a segment has been written to a device.
MT safe.
the callback to set
Tell the ringbuffer about the device's channel positions. This must be called in when the ringbuffer is acquired.
the device channel positions
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.
property to disable
boolean that specifies whether to disable the controller or not.
This function is used to disable all controlled properties of the object
for
some time, i.e. gst_object_sync_values() will do nothing.
boolean that specifies whether to disable the controller or not.
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.
the new control-rate in nanoseconds.
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.
name of the key
data to associate with that key
Set the ringbuffer to flushing mode or normal mode.
MT safe.
the new mode
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.
new name of object
Sets a property on an object.
the name of the property to set
the value
Make sure that the next sample written to the device is
accounted for as being the sample
sample written to the
device. This value will be used in reporting the current
sample position of the ringbuffer.
This function will also clear the buffer with silence.
MT safe.
the sample number to set
Start processing samples from the ringbuffer.
Remove a specified datum from the object's data associations, without invoking the association's destroy handler.
name of the key
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().
A #GQuark, naming the user data pointer
Stop processing samples from the ringbuffer.
Returns a suggestion for timestamps where buffers should be split to get best controller results.
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.
the time that should be processed
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.
Clear the parent of object,
removing the associated reference.
This function decreases the refcount of object
.
MT safe. Grabs and releases object'
s lock.
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.
Allocate the resources for the ringbuffer. This function fills in the data pointer of the ring buffer with a valid #GstBuffer to which samples can be written.
the specs of the buffer
Activate buf
to start or stop pulling data.
MT safe.
the new mode
Clear all samples from the ringbuffer.
MT safe.
Close the audio device associated with the ring buffer. The ring buffer should already have been released via gst_audio_ring_buffer_release().
Commit in_samples
samples pointed to by data
to the ringbuffer buf
.
in_samples
and out_samples
define the rate conversion to perform on the
samples in data
. For negative rates, out_samples
must be negative and
in_samples
positive.
When out_samples
is positive, the first sample will be written at position sample
in the ringbuffer. When out_samples
is negative, the last sample will be written to
sample
in reverse order.
out_samples
does not need to be a multiple of the segment size of the ringbuffer
although it is recommended for optimal performance.
accum
will hold a temporary accumulator used in rate conversion and should be
set to 0 when this function is first called. In case the commit operation is
interrupted, one can resume the processing by passing the previously returned
accum
value back to this function.
MT safe.
the sample position of the data
the data to commit
the number of samples to write to the ringbuffer
accumulator for rate conversion.
Get the number of samples queued in the audio device. This is usually less than the segment size but can be bigger when the implementation uses another internal buffer between the audio device.
For playback ringbuffers this is the amount of samples transferred from the ringbuffer to the device but still not played.
For capture ringbuffers this is the amount of samples in the device that are not yet transferred to the ringbuffer.
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.
Open the audio device associated with the ring buffer. Does not perform any setup on the device. You must open the device before acquiring the ring buffer.
Pause processing samples from the ringbuffer.
Free the resources of the ringbuffer.
Start processing samples from the ringbuffer.
Stop processing samples from the ringbuffer.
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.
#GClosure to watch
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.
Print debug info about the buffer sized in spec
to the debug log.
the spec to debug
Print debug info about the parsed caps in spec
to the debug log.
the spec to debug
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.
the #GObject that signalled the notify.
a #GstObject that initiated the notify.
a #GParamSpec of the property.
a set of user-specified properties to exclude or %NULL to show all changes.
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().
any interface vtable for the interface, or the default vtable for the interface
name of a property to look up.
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.
any interface vtable for the interface, or the default vtable for the interface.
the #GParamSpec for the new property
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().
any interface vtable for the interface, or the default vtable for the interface
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.
the type id of the #GObject subtype to instantiate
an array of #GParameter
Parse caps
into spec
.
a spec
a #GstCaps
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.
pointer to a place of a #GstObject to replace
a new #GstObject
This object is the base class for audio ringbuffers used by the base audio source and sink classes.
The ringbuffer abstracts a circular buffer of data. One reader and one writer can operate on the data from different threads in a lockfree manner. The base class is sufficiently flexible to be used as an abstraction for DMA based ringbuffers as well as a pure software implementations.