TSignalVariableRateConverter Class

class TSignalVariableRateConverter : public TSignalRateConverter;

Variable frequency rate converter.

Use the component to vary the sampling frequency as a function of time. The function is passed as a vector of sampling points specified at the sampling frequency of the input signal with RateVector property.

The component uses a fixed filter bank and delivers aliasing free output, with linear phase and user definable attenuation of the lowpass filters and witdh of the FIR transition band in the final signal.

Fixed filter bank allows for exceptional performance as it can take full advantage code vectorization.

The filter bank is specified by defining the MaxFactor and MinFactor properties, which define the maximum and minimum factor by which the sampling frequency can change with the reference to the sampling frequency of the input signal. Within this range, the sampling frequency can then be freely adjusted from one sample to the next without danger of aliasing.

The performance of the rate conversion process depends upon the MaxFactor/MinFactor where the processing load will increase nearly linearly with the increase of these factors.

Constructors

Name	Description
TSignalVariableRateConverter (2)

Destructors

Name	Description
~TSignalVariableRateConverter

Properties

Name	Type	Description
Active	bool	Set active to false to suppress the propagation of the Pull request and the subsequent call to the Update method.
AudioSignal	bool	Enable when the signal processed is Audio signal.
BandWidth	double	Return the bandwidth of the signal.
BandwidthH	double	Returns the upper bandwidth edge of the signal.
BandwidthL	double	Returns the lower bandwidth edge of the signal.
BlockAssign	bool	Block streaming of specific properties when storing only a "template".
ChannelCount	int	Get or set the number of channels multiplexed in the data property.
Complex	bool	Set this property to true, to request computation using complex numbers.
Continuous	bool	If True, the component will pass on the udpate request to the connected component.
Data	TVec*	Stores the result of the processing.
Dt	double	Time between two consecutive samples.
EditorActive	bool	Returns True, if the component editor is displayed.
Factor	double	Factor by which to change the sampling frequency of the signal connected to the Input property.
FilterDelay	double	Returns the filter delay in number of samples of the final sampling frequency.
FloatPrecision	TMtxFloatPrecision	Set this property to request computation in 32bit/64bit precision with real/complex numbers.
FloatPrecisionLock	bool	Set this property to true to lock changes to FloatPrecision property.
HalfBand	bool	The bandwidth will be halved during downsampling.
HzRes	double	Frequency resolution obtained, if an FFT algorithm would be run on the data.
Input	TSignal*
Inputs	TSignalCollection*
IsDouble	bool	Set this property to false, to request computation in 32bit floating point precision, 64bit, if true.
ItemNumber	int	Number to label the object when it is an item in the List.
Length	int	Get or set the length of the signal in samples.
Marks	TMarkList*	Stores the time stamps and amplitude of selected samples.
MaxAmplt	double	Stores the maximum amplitude of the signal found by the MinMax method.
MaxFactor	double	Specifies the maximum Factor up to which the rate converter can vary the sampling frequency, without introducing aliasing.
MaxX	double	Use the MaxX property to store the time stamp (in seconds) of the right most sample.
MinAmplt	double	Stores the minimum amplitude of the signal found by the MinMax method.
MinFactor	double	Specifies the minimum Factor down to which the rate converter can vary the sampling, without introducing aliasing.
MinX	double	Use the MinX property to store the time stamp of the left-most sample.
MultiChannel	bool	Set MultiChannel to True, if Inputs property will be published, and Input property will remain hidden.
Name	DewString
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. Use this event to update any associated charts or graphs or result tables.
OnGetInput	tNotifyEvent	If the Input property is not assigned, the component will call OnGetInput.
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. The ParamUpdate method is usually called by component editors when a value was changed by the user and the editor was "Live".
PipeDirty	bool
PipeState	TPipeState	Returns the state of the pipe after the last update.
RateVector	TVec*	Defines sample positions at which to resample the Input signal.
Reference	TReferenceList*	Stores a list of components that have to be notified, when this component is destroyed.
Ripple	double	Defines the ripple of the passband and of the stopband of the FIR lowpass filter used for interpolation.
SamplingFrequency	double	Defines the sampling frequency of the signal.
SamplingTime	double	The length of the signal in seconds.
ScaleFactor	double	Additional scaling factor which is applied without extra performance cost.
SuspendNotifyUpdate	bool	Set this property to True, to prevent calling OnNotifyUpdate from the Update Method.
TransBW	double	Defines the width of the transition band of the FIR filter used for interpolation/decimation.
UsesInputs	bool	Set it to True to indicate, that valid signals will be connected to the Input or Inputs properties.

Methods

Name	Description
AllowStreaming
Append	Appends Sample to the end of the signal.
Assign
AssignTemplate	Assign values of "template-like" published properties from Source.
Copy	Copies signal Data and sampling frequency information.
Crest	Compute the CREST parameter.
DetectChannelCount
EditorClass	To be overriden in descendanr classses.
get_CValues
get_Values
GetInput
GetInputs
Initialize
InputsDirty	If all Inputs[i] are dirty the function returns true.
InternalPull	When called, the method will pass Update requests recursively to all connected objects.
Invalidate	Notifies all connected components that this component has fresh data.
LoadFromStream	Load the component from Src stream.
LoadTemplateFromFile	Load a template from file.
LoadTemplateFromStream	Load a template from stream.
MarksToStrings	Convert marks to strings.
MinMax	Find minimum and maximum amplitude and store the result in the MinAmplt and MaxAmplt properties.
ParamUpdate	The method can be assigned to some other component even handler, as a notification that a parameter has changed and that Self should consider a recalculation.
Peak	Find the maximum deviation of the signal from its mean value.
PipeReset	Recursively processes all connected components backward and calls Reset method.
Pull	Request recalculation of the entire chain of all connected components.
PullUntilEnd	Calls Pull until pipeEnd is returned.
ReferenceRemoved
Reset	Reset all delay lines.
SaveTemplateToFile	Save template to file.
SaveTemplateToStream	Save template to stream.
SaveToStream	Save the component to Dst stream.
set_CValues
set_Values
SetComplex
SetFloatPrecision
SetInputs
SetIsDouble
Size	Assign the size of the signal from Src.
Update	Request recalculation of the data and place the result in Self.
UpdateNotify	Call this method only, if SuspendNotifyUpdate is True.
Values
ValuesToStrings	Convert values to strings.

Operators

Name	Description
operator[]

Fields

Name	Type	Description
Tag	intptr_t