Shifts an audio signal forward in time by a fixed amount. More...

#include <hart_time_shift.hpp>

Inheritance diagram for TimeShift< SampleType >:

Public Member Functions
	TimeShift (double delaySeconds)
	Creates a TimeShift processor with a fixed delay.

	TimeShift (const TimeShift &other)
	Creates a TimeShift processor by copying other one.

	TimeShift (TimeShift &&other) noexcept
	Creates a TimeShift processor by moving other one.

TimeShift &	operator= (const TimeShift &other)
	Creates a TimeShift processor by copying other one.

TimeShift &	operator= (TimeShift &&other) noexcept
	Creates a TimeShift processor by moving other one.

	~TimeShift () override=default

void	prepare (double sampleRateHz, size_t numInputChannels, size_t numOutputChannels, size_t) override
	Prepare for processing.

void	process (const AudioBuffer< SampleType > &input, AudioBuffer< SampleType > &output, const EnvelopeBuffers &, ChannelFlags) override
	Processes the audio.

bool	supportsEnvelopeFor (int) const override
	Tells whether this effect accepts automation envelopes for a particular parameter.

bool	supportsChannelLayout (size_t numInputChannels, size_t numOutputChannels) const override
	Tells the runner (host) whether this effect supports a specific i/o configuration.

bool	supportsSampleRate (double sampleRateHz) const override
	Tells whether this effect supports given sample rate.

void	represent (std::ostream &stream) const override
	Makes a text representation of this DSP effect for test failure outputs.

void	setValue (int, double) override
	Sets DSP value.

	HART_DSP_COPYABLE (TimeShift)

	HART_DSP_MOVABLE (TimeShift)

Public Member Functions inherited from DSP< SampleType, TimeShift< SampleType > >
TimeShift< SampleType > &	withEnvelope (int paramId, Envelope &&envelope) &
	Adds envelope to a specific parameter by moving it.

TimeShift< SampleType > &&	withEnvelope (int paramId, Envelope &&envelope) &&
	Adds envelope to a specific parameter by moving it.

TimeShift< SampleType > &	withEnvelope (int paramId, const Envelope &envelope) &
	Adds envelope to a specific parameter by copying it.

TimeShift< SampleType > &&	withEnvelope (int paramId, const Envelope &envelope) &&
	Adds envelope to a specific parameter by copying it.

virtual std::unique_ptr< DSPBase< SampleType > >	move () override
	Returns a smart pointer with a moved instance of this object.

TimeShift< SampleType > &	atChannels (std::initializer_list< size_t > channelsToProcess) &
	Makes this DSP process only specific channels, and ignore the rest.

TimeShift< SampleType > &&	atChannels (std::initializer_list< size_t > channelsToProcess) &&
	Makes this DSP process only specific channels, and ignore the rest.

TimeShift< SampleType > &	atChannel (size_t channelToProcess) &
	Makes this DSP process only specific channels, and bypass the rest.

TimeShift< SampleType > &&	atChannel (size_t channelToProcess) &&
	Makes this DSP process only specific channels, and bypass the rest.

TimeShift< SampleType > &	atAllChannels () &
	Makes this DSP apply to all channels.

TimeShift< SampleType > &&	atAllChannels () &&
	Makes this DSP apply to all channels.

TimeShift< SampleType > &	atAllChannelsExcept (std::initializer_list< size_t > channelsToSkip) &
	Makes this DSP process only specific channels, and bypass the rest.

TimeShift< SampleType > &&	atAllChannelsExcept (std::initializer_list< size_t > channelsToSkip) &&
	Makes this DSP process only specific channels, and bypass the rest.

Public Member Functions inherited from DSPBase< SampleType >
virtual void	reset ()
	Resets to initial state.

virtual double	getValue (int) const
	Retrieves DSP value.

virtual std::unique_ptr< DSPBase< SampleType > >	copy () const
	Returns a smart pointer with a copy of this object.

virtual	~DSPBase ()=default
	Destructor.

	DSPBase ()=default
	Default constructor.

	DSPBase (const DSPBase &other)
	Copies from another DSP effect instance.

	DSPBase (DSPBase &&other) noexcept
	Move constructor.

DSPBase &	operator= (const DSPBase &other)
	Copies from another DSP effect instance.

DSPBase &	operator= (DSPBase &&other) noexcept
	Move assignment.

bool	hasEnvelopeFor (int paramId)
	Checks if there's an automation envelope attached to a specific parameter.

void	prepareWithEnvelopes (double sampleRateHz, size_t numInputChannels, size_t numOutputChannels, size_t maxBlockSizeFrames)
	Prepares all the attached envelopes and the effect itself for processing.

void	resetWithEnvelopes ()
	Resets the DSP instance, and all associated Envelopes.

ChannelFlags	getChannelsToProcess ()
	Returns a structure indicating which channels should be processed by this DSP.

void	processWithEnvelopes (const AudioBuffer< SampleType > &input, AudioBuffer< SampleType > &output)
	Renders all the automation envelopes and processes the audio.

void	representWithActiveChannels (std::ostream &stream) const
	Makes a text representation of this DSP with optional "atChannels" appendix.

Additional Inherited Members
Protected Attributes inherited from DSPBase< SampleType >
std::unordered_map< int, std::unique_ptr< Envelope > >	m_envelopes

ChannelFlags	m_channelsToProcess {true}

Related Symbols inherited from DSP< SampleType, TimeShift< SampleType > >
std::ostream &	operator<< (std::ostream &stream, const DSPBase< SampleType > &dsp)
	Prints readable text representation of the DSP object into the I/O stream.

Detailed Description

template<typename SampleType>
class hart::TimeShift< SampleType >

Shifts an audio signal forward in time by a fixed amount.

Delays the input signal by a specified duration, expressed in seconds. Internally, the delay is converted to an integer number of frames based on the current sample rate, so it soesn't do sub-frame (fractional) elays. This DSP is a low-level utility intended for testing and signal alignment purposes, such as compensating for latency in other processors. It performs a pure time shift with no feedback or dry/wet mixing. The output is zero-filled until the internal buffer is primed. Delay time is fixed and cannot be changed after construction or copy/move assignment. The delay is identical across all channels, and processing is only supported when the number of input and output channels matches. It is encouraged to use it in conjunction with hart::Impulse signal, although other signal types may also be appropriate.

Exceptions

hart::ValueError for negative or zero delay (in seconds or frames)

Template Parameters

SampleType Floating point sample type, typecally float or double.

Definition at line 28 of file hart_time_shift.hpp.

Constructor & Destructor Documentation

◆ TimeShift() [1/3]

template<typename SampleType >

TimeShift ( double delaySeconds )

inline

Creates a TimeShift processor with a fixed delay.

Parameters

delaySeconds Delay duration in seconds. Must be greater than zero. The delay value is converted to an integer number of frames during prepare(), based on the provided sample rate. Values that resolve to zero frames are rejected.

Exceptions

hart::ValueError for negative or zero delay (in seconds or frames)

Definition at line 37 of file hart_time_shift.hpp.

◆ TimeShift() [2/3]

template<typename SampleType >

TimeShift ( const TimeShift< SampleType > & other )

inline

Creates a TimeShift processor by copying other one.

The entire state, included internal delay byffers' content is copied as well

Parameters

other TimeShift to copy from

Definition at line 47 of file hart_time_shift.hpp.

◆ TimeShift() [3/3]

template<typename SampleType >

TimeShift ( TimeShift< SampleType > && other )

inlinenoexcept

Creates a TimeShift processor by moving other one.

The entire state, included internal delay byffers' content is moved as well

Parameters

other TimeShift to move from

Definition at line 60 of file hart_time_shift.hpp.

◆ ~TimeShift()

template<typename SampleType >

~TimeShift ( )

overridedefault

Member Function Documentation

◆ operator=() [1/2]

template<typename SampleType >

TimeShift & operator= ( const TimeShift< SampleType > & other )

inline

Creates a TimeShift processor by copying other one.

The entire state, included internal delay byffers' content is copied as well

Parameters

other TimeShift to copy from

Definition at line 76 of file hart_time_shift.hpp.

◆ operator=() [2/2]

template<typename SampleType >

TimeShift & operator= ( TimeShift< SampleType > && other )

inlinenoexcept

Creates a TimeShift processor by moving other one.

The entire state, included internal delay byffers' content is moved as well

Parameters

other TimeShift to move from

Definition at line 95 of file hart_time_shift.hpp.

◆ prepare()

template<typename SampleType >

void prepare	(	double	sampleRateHz,
		size_t	numInputChannels,
		size_t	numOutputChannels,
		size_t	maxBlockSizeFrames
	)

inlineoverridevirtual

Prepare for processing.

In real-time DSP, such methods are usually used for allocating memory and other non-realtime-safe and heavyweight operations. But keep in mind that that HART does not do real-time processing, so this merely follows common real-time DSP design conventions, where non-realtime operations are done in a separate callback like this one. This method is guaranteed to be called after supportsChannelLayout() and supportsSampleRate(), but before process(). It is guaranteed that the number of input and output channels obeys supportsChannelLayout() and supportsSampleRate() preferences. It is guaranteed that all subsequent process() calls will be in line with the arguments received in this callback.

Parameters

sampleRateHz	sample rate at which the audio should be interpreted and processed
numInputChannels	Number of input channels
numOutputChannels	Number of output channels
maxBlockSizeFrames	Maximum block size in frames (samples)

Implements DSPBase< SampleType >.

Definition at line 117 of file hart_time_shift.hpp.

◆ process()

template<typename SampleType >

void process	(	const AudioBuffer< SampleType > &	input,
		AudioBuffer< SampleType > &	output,
		const EnvelopeBuffers &	envelopeBuffers,
		ChannelFlags	channelsToProcess
	)

inlineoverridevirtual

Processes the audio.

Depending on circumstances, this callback will either be called once to process an entire piece of audio from start to finish, or called repeatedly, one block at a time (see AudioTestBuilder::withBlockSize()). All audio blocks except the last one are guaranteed to be equal to maxBlockSizeFrames set in prepare() callback. It is guaranteed that input and output buffers are equal in length in frames (samples) to each, but they might have different number of channels. Use supportsChannelLayout() to indicate whether the effect supports a specific i/o configuration or not, as it will be called before prepare(). It is guaranteed that envelopeBuffers will only contain the values for all attached envelopes for this instance of DSP effect, and will not contain any data (including key with empty item) if there's no envelope attached to a specific parameter ID in this effects's instance. It will never contain envelopes for IDs that get rejected by supportsEnvelopeFor(). Each vector in the envelopeBuffers map is guaranteed to be at least as large as input (and output) block. For partial blocks, only the first input.getNumFrames() elements contain valid data for the current block; the rest may be stale or uninitialized. DSP implementations are expected to ignore values beyond that index range.

Note: This method may be called in a replacing manner, i. e. input and output may be references to the same object.

Warning: Remember that the very last block of audio is almost always smaller than the block size set in prepare(), so be careful with buffer bounds.

Note: Note that this method does not have to be real-time safe, as all rendering always happens offline. Also note that, unlike real-time audio applications, this method is called on the same thread as all others like prepare().

Parameters

input	Input audio block
output	Output audio block
envelopeBuffers	Envelope values for this block, see EnvelopeBuffers
channelsToProcess	Channels that need processing. Process channels that are marked `true`, bypass ones marked `false`.

Implements DSPBase< SampleType >.

Definition at line 143 of file hart_time_shift.hpp.

◆ supportsEnvelopeFor()

template<typename SampleType >

bool supportsEnvelopeFor ( int ) const

inlineoverridevirtual

Tells whether this effect accepts automation envelopes for a particular parameter.

Parameters

paramId Some ID that your subclass understands

Returns: true if your subclass can process automation for this parameter, false otherwise

Reimplemented from DSPBase< SampleType >.

Definition at line 168 of file hart_time_shift.hpp.

◆ supportsChannelLayout()

template<typename SampleType >

bool supportsChannelLayout	(	size_t	numInputChannels,
		size_t	numOutputChannels
	)		const

inlineoverridevirtual

Tells the runner (host) whether this effect supports a specific i/o configuration.

It is guaranteed that the effect will not receive unsupported number of channels in process(). However, it is not always possible to handle gracefully channel layout being unsupported, so in some circumstances it can cause an exception or a test failure. This method is guaranteed to be called at least once before prepare()

Implements DSPBase< SampleType >.

Definition at line 173 of file hart_time_shift.hpp.

◆ supportsSampleRate()

template<typename SampleType >

bool supportsSampleRate ( double ) const

inlineoverridevirtual

Tells whether this effect supports given sample rate.

It is guaranteed to be called before prepare()

Parameters

sampleRateHz Sample rate in question

Returns: true if effect is capable of interpreting and processing in a given sample rate, false otherwise

Reimplemented from DSPBase< SampleType >.

Definition at line 178 of file hart_time_shift.hpp.

◆ represent()

template<typename SampleType >

void represent ( std::ostream & stream ) const

inlineoverridevirtual

Makes a text representation of this DSP effect for test failure outputs.

It is strongly encouraged to follow python's repr() conventions for returned text - basically, put something like "MyClass(value1, value2)" (with no quotes) into the stream whenever possible, or "<Readable info in angled brackets>" otherwise. Also, use built-in stream manipulators like dbPrecision wherever applicable. Use HART_DEFINE_GENERIC_REPRESENT() to get a basic implementation for this method.

Parameters

[out] stream Output stream to write to

Implements DSPBase< SampleType >.

Definition at line 183 of file hart_time_shift.hpp.

◆ setValue()

template<typename SampleType >

void setValue	(	int	paramId,
		double	value
	)

inlineoverridevirtual

Sets DSP value.

Parameters

paramId	Some ID that your subclass understands; use of enums is encouraged for readability
value	Value of the param in an appropriate unit; use of SI units is encouraged (i.e. s instead of ms. Hz instead of kHz) to make better use of unit literals (see Units)

Warning: This method is only called to set a fixed value before processing, and is not called to do automation (via hart::Envelope) If you want your class to support automation for a specific parameter, override supportsEnvelopeFor(), and then use envelopeBuffers provided in process() callback.

Implements DSPBase< SampleType >.

Definition at line 188 of file hart_time_shift.hpp.

◆ HART_DSP_COPYABLE()

template<typename SampleType >

HART_DSP_COPYABLE ( TimeShift< SampleType > )

◆ HART_DSP_MOVABLE()

template<typename SampleType >

HART_DSP_MOVABLE ( TimeShift< SampleType > )

The documentation for this class was generated from the following file:

include/dsp/hart_time_shift.hpp

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ TimeShift() [1/3]

◆ TimeShift() [2/3]

◆ TimeShift() [3/3]

◆ ~TimeShift()

Member Function Documentation

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ prepare()

◆ process()

◆ supportsEnvelopeFor()

◆ supportsChannelLayout()

◆ supportsSampleRate()

◆ represent()

◆ setValue()

◆ HART_DSP_COPYABLE()

◆ HART_DSP_MOVABLE()