TSignalCoreAudioOut Class

type TSignalCoreAudioOut = class(TSignalCoreAudio);

Audio playback component based on WASAPI drivers.

Component uses CoreAudio audio drivers for playback. Output channel data is obtained from Inputs property which must be assigned before the playback starts. Typically <see cref="TSignalDemuxList"/> would be assigned to Inputs and TSignalDemuxList.Inputs to <see cref="TSignalRead"/>. Before the playback can start: The SamplingFrequency for the CoreAudio component must always be set manually and needs to be supported by the driver. The component will perform rate conversion if input signal does not have the same SamplingFrequency. ChannelCount and Inputs.Count need to match. An exception is the mono single channel signal. Mono signal will always play on all channels. <see cref="Precision"/> property must be set to reflect the format of the data to be played back. In case of 16bit, it should be set to prSmallInt. If data is stored as double precision and normalized to have a maximum value of 1 then this setting should be prDouble. Define <see cref="PrecisionHw"/> property. This is the precision of the audio engine. Choose values supported by the audio drivers and hardware. Precision and PrecisionHW are used together to determine the correct scaling. * Exclusive can be set to true or false. When access to the device is exclusive, the latency can be less, audio quality higher, but audio device cannot be shared with other applications. Most importantly, all pre and post processing filters used by Windows are bypassed. (Like Dolby Digital, Room Correction, etc...) Once a new buffer is ready, the driver will call <see cref="OnProcessRealTime"/> event. This event is executed within the drivers thread and should not interact directly with the user interface. From this event <see cref="OutputBuffers"/> can be accessed and processed with minimum delay time.

Properties

Name	Type	Description
Active	Boolean	Set active to false to suppress the propagation of the Pull request and the subsequent call to the Update method.
BlockAssign	Boolean	Block streaming of specific properties when storing only a "template".
Complex	Boolean	Set this property to true, to request computation using complex numbers.
Continuous	Boolean	If True, the component will pass on the udpate request to the connected component.
Count	Integer	Defines the size of the list.
DeviceIndex	integer	Returns the index of the currently open CoreAudio driver in the list of available drivers.
DisabledOrDisconnected	boolean	Returns true, if the hardware appears disabled or disconnected.
EditIndex	Integer	Specifies index of the item in the list for which to display the design-time editor.
EditorActive	Boolean	Returns True, if the component editor is displayed.
First	TMtxComponent	Returns the pointer to Items[0].
FloatPrecision	TMtxFloatPrecision	Set this property to request computation in 32bit/64bit precision with real/complex numbers.
FloatPrecisionLock	Boolean	Set this property to true to lock changes to FloatPrecision property.
IsDouble	Boolean	Set this property to false, to request computation in 32bit floating point precision, 64bit, if true.
Item	TSignal	Access TSignal objects by Index.
Items	TSignalChannel	Default array property allows access to individual list items.
ItemsCollection	TMtxComponentCollection	Content serialization and designer editor support.
Last	TMtxComponent	Returns Items[Count - 1].
OnAfterUpdate	TNotifyEvent	The event is triggered after the call to the Update method.
OnBeforeUpdate	TNotifyEvent	The event is triggered just before the call to the Update method.
OnDisplayUpdate	TNotifyEvent	The event is triggered after the OnAfterUpdate event.
OnItemAdd	TMtxComponentAddEvent	Event triggered after a new item has been added.
OnItemDelete	TMtxComponentDeleteEvent	Event triggered before the Item will be deleted.
OnNotifyUpdate	TNotifyEvent	The event is called after a call to InternalUpdate, OnAfterUpdate and OnDisplayUpdate from within the Update method.
OnParameterUpdate	TNotifyEvent	The event is triggered when ParamUpdate method is called.
Paused	boolean	Set this property to True, to pause the playback and/or recording.
ProcessingTime	double	Returns processing time of the real-time loop in miliseconds.
PropagateTemplate	Boolean	Defines how TMtxComponentList.Propagate will proparage properties.
Reference	TReferenceList	Stores a list of components that have to be notified, when this component is destroyed.
SuspendNotifyUpdate	Boolean	Set this property to True, to prevent calling OnNotifyUpdate from the Update Method.
Volume	single	Set this property to to change the playback/recording volume.

Methods

Name	Description
ActualLatency	Returns actual buffer latency in miliseconds.
AllowStreaming	Returns the negatated value of BlockAssign.
Assign	Assign values of all published properties from Source.
AssignTemplate	Assign values of "template-like" published properties from Source.
BufferStats	See abstract method TSignalCoreAudio.BufferStats for more info.
Clear	Deletes all items from the list.
Create
Delete	Deletes the item from the list.
Destroy
EditorClass	To be overriden in descendanr classses.
ElapsedSamples	Returns total number of samples elapsed since start.
ElapsedTime	Returns time elapsed since start in seconds.
Exchange	Swaps the position of two items in the Items array.
Extract	Extracts the item from the list.
GetDeviceList	Returns a list of CoreAudio devices.
GetDriverLatency	Returns latency in miliseconds as reported by the driver.
GetSupportedPrecisionHWs	Returns list of supported PrecisionHW values.
GetSupportedSamplingFrequencies	Returns list of supported sampling frequencies for the currently selected PrecisionHW.
Insert	Inserts an item at position Index
IsFormatSupported	Returns true if current setting of SamplingFrequency, ChannelCount and PrecisionHW properties is valid for the selected device.
LoadFromStream	Load the component from Src stream.
LoadTemplateFromFile	Load a template from file.
LoadTemplateFromStream	Load a template from stream.
MatchInputs	Match the connections of Inputs with the component.
MonitorOutput	Returns most current data, just to be played back.
MonitorOutputBuffer	Thread safe method to obtain CoreAudio buffer for monitoring.
Move	Changes the position of an item in the Items array.
OutputBufferSkipped	Returns number of output buffers skipped due to CPU overload.
Propagate (2)	Propagates the settings of the component at SrcIndex to all other components.
Pull	Distribute Pull request to all objects in the list.
PullBuffer	Call to fill extended buffer exactly once from Inputs.
PullUntilEnd	Calls Pull until pipeEnd is returned.
RateConverterFilterDelay	Returns rate conversion filter delay in number of samples.
RefillBuffers
RefreshDevices
Remove	Deletes the first reference to the Item parameter from the Items array.
Renumerate	Assign consecutive numbers to individual items.
Reset	Reset is called after loading the data from stream or file.
Rotate	Rotate the list up or down.
SaveTemplateToFile	Save template to file.
SaveTemplateToStream	Save template to stream.
SaveToStream	Save the component to Dst stream.
Start	Start the recording or playback.
Stop	Stop the recording or playback.
StopGracefully	Stop the recording or playback.
Update	Distribute Update request to all objects in the list.
UpdateNotify	Call this method only, if SuspendNotifyUpdate is True.

Constants

Name	Type	Description
smplCount	integer