ThresholdCrossingDetector Class Reference

Public Types
enum	SearchStates { SEARCHING_FOR_FIRST_THRESHOLD_CROSSING =0, SEARCHING_FOR_SECOND_THRESHOLD_CROSSING, NO_SEARCH_GATE_TIME_OUT }
enum	ThresholdCrossingModes {   UPPER_THRESHOLD_CROSSING =0, LOWER_THRESHOLD_CROSSING, UPPER_OR_LOWER_THRESHOLD_CROSSING, UPPER_THEN_LOWER_THRESHOLD_CROSSING,   LOWER_THEN_UPPER_THRESHOLD_CROSSING }
enum	AnalysisModes { RAW_DATA_ANALYSIS_MODE =0, MOVING_OFFSET_ANALYSIS_MODE, DERIVATIVE_ANALYSIS_MODE }
enum	DetectionTimeoutMode { TIMEOUT_COUNTER =0, HYSTERESIS_THRESHOLD }

Public Member Functions
	ThresholdCrossingDetector (UINT analysisMode=RAW_DATA_ANALYSIS_MODE, UINT thresholdCrossingMode=UPPER_THRESHOLD_CROSSING, UINT detectionTimeoutMode=TIMEOUT_COUNTER, Float lowerThreshold=-1, Float upperThreshold=1, Float hysteresisThreshold=0, UINT searchWindowSize=20, UINT searchTimeoutDuration=1000, UINT offsetFilterSize=10)
	~ThresholdCrossingDetector ()
	ThresholdCrossingDetector (const ThresholdCrossingDetector &rhs)
ThresholdCrossingDetector &	operator= (const ThresholdCrossingDetector &rhs)
bool	update (const Float x)
bool	reset ()
bool	triggerSearchTimeout ()
bool	getThresholdCrossingDetected () const
bool	getEnableSearch () const
UINT	getAnalysisMode () const
UINT	getThresholdCrossingMode () const
UINT	getSearchWindowSize () const
UINT	getOffsetFilterSize () const
UINT	getSearchWindowIndex () const
UINT	getSearchTimeoutCounter ()
UINT	getSearchTimeoutDuration () const
Float	getAnalysisValue () const
Float	getUpperThreshold () const
Float	getLowerThreshold () const
Float	getHysteresisThreshold () const
bool	setEnableSearch (const bool enableSearch)
bool	setAnalysisMode (const UINT analysisMode)
bool	setThresholdCrossingMode (const UINT thresholdCrossingMode)
bool	setSearchWindowSize (const UINT searchWindowSize)
bool	setOffsetFilterSize (const UINT offsetFilterSize)
bool	setSearchTimeoutDuration (const UINT searchTimeoutDuration)
bool	setDetectionTimeoutMode (const UINT detectionTimeoutMode)
bool	setLowerThreshold (const Float lowerThreshold)
bool	setUpperThreshold (const Float upperThreshold)
bool	setHysteresisThreshold (const Float hysteresisThreshold)

Protected Attributes
Float	analysisValue
Float	lowerThreshold
Float	upperThreshold
Float	hysteresisThreshold
bool	enableSearch
bool	thresholdCrossingDetected
unsigned int	analysisMode
unsigned int	thresholdCrossingMode
unsigned int	detectionTimeoutMode
unsigned int	searchTimeoutDuration
unsigned int	searchWindowSize
unsigned int	searchWindowIndex
unsigned int	offsetFilterSize
unsigned int	currentSearchState
Timer	searchTimeoutCounter
MovingAverageFilter	movingAverageFilter
Derivative	derivative

Detailed Description

Definition at line 38 of file ThresholdCrossingDetector.h.

Constructor & Destructor Documentation

GRT_BEGIN_NAMESPACE ThresholdCrossingDetector::ThresholdCrossingDetector	(	UINT	analysisMode = RAW_DATA_ANALYSIS_MODE,
		UINT	thresholdCrossingMode = UPPER_THRESHOLD_CROSSING,
		UINT	detectionTimeoutMode = TIMEOUT_COUNTER,
		Float	lowerThreshold = -1,
		Float	upperThreshold = 1,
		Float	hysteresisThreshold = 0,
		UINT	searchWindowSize = 20,
		UINT	searchTimeoutDuration = 1000,
		UINT	offsetFilterSize = 10
	)

Default Constructor.

Parameters

analysisMode	sets the algorithm used to detect threshold crossings, this should be one of the AnalysisMode enums
thresholdCrossingMode	sets the threshold crossing mode, this should be one of the ThresholdCrossingModes enums
lowerThreshold	sets the lower threshold level
upperThreshold	sets the upper threshold level
searchWindowSize	sets the size of the search window used to detect UPPER_THEN_LOWER_THRESHOLD_CROSSING or LOWER_THEN_UPPER_THRESHOLD_CROSSING
searchTimeoutDuration	sets the duration (in samples) that the threshold detector will ignore any new threshold crossings after detecting a valid threshold crossing
offsetFilterSize	sets the size of the moving average filter used to offset the input value (if the analysisMode is set to MOVING_OFFSET_ANALYSIS_MODE)

Definition at line 26 of file ThresholdCrossingDetector.cpp.

ThresholdCrossingDetector::~ThresholdCrossingDetector

(

)

Default Destructor.

Definition at line 66 of file ThresholdCrossingDetector.cpp.

ThresholdCrossingDetector::ThresholdCrossingDetector

(

const ThresholdCrossingDetector &

rhs

)

Copy Constructor. Copies the data from the rhs instance to this instance.

Parameters

const

ThresholdCrossingDetector &rhs: the right hand instance from which the data will be copied to this instance

Definition at line 47 of file ThresholdCrossingDetector.cpp.

Member Function Documentation

UINT ThresholdCrossingDetector::getAnalysisMode

(

)

const

Returns

returns the current analysis mode, this will be one of the AnalysisModes enums

Definition at line 283 of file ThresholdCrossingDetector.cpp.

Float ThresholdCrossingDetector::getAnalysisValue

(

)

const

Returns

gets the most recent analysis value used to compute the threshold crossing

Definition at line 311 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::getEnableSearch

(

)

const

Returns

returns true if the search is enabled, false otherwise

Definition at line 279 of file ThresholdCrossingDetector.cpp.

Float ThresholdCrossingDetector::getHysteresisThreshold

(

)

const

Returns

gets the hysteresis threshold value

Definition at line 323 of file ThresholdCrossingDetector.cpp.

Float ThresholdCrossingDetector::getLowerThreshold

(

)

const

Returns

gets the lower threshold value

Definition at line 319 of file ThresholdCrossingDetector.cpp.

UINT ThresholdCrossingDetector::getOffsetFilterSize

(

)

const

Returns

returns the size of the moving average filter used to offset the input value, this is only used if the analysisMode is MOVING_OFFSET_ANALYSIS_MODE

Definition at line 295 of file ThresholdCrossingDetector.cpp.

UINT ThresholdCrossingDetector::getSearchTimeoutCounter

(

)

Returns

gets the current search timeout counter value

Definition at line 303 of file ThresholdCrossingDetector.cpp.

UINT ThresholdCrossingDetector::getSearchTimeoutDuration

(

)

const

Returns

gets the search timeout duration

Definition at line 307 of file ThresholdCrossingDetector.cpp.

UINT ThresholdCrossingDetector::getSearchWindowIndex

(

)

const

Returns

gets the current index in the search window when the algorithm is looking for the second threshold crossing for UPPER_THEN_LOWER_THRESHOLD_CROSSING or LOWER_THEN_UPPER_THRESHOLD_CROSSING

Definition at line 299 of file ThresholdCrossingDetector.cpp.

UINT ThresholdCrossingDetector::getSearchWindowSize

(

)

const

Returns

returns the search window size, this is only used if the thresholdCrossingMode is UPPER_THEN_LOWER_THRESHOLD_CROSSING or LOWER_THEN_UPPER_THRESHOLD_CROSSING

Definition at line 291 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::getThresholdCrossingDetected

(

)

const

This function returns true if a threshold crossing was detected during the last update.

Returns

returns true if a threshold crossing was detected, false otherwise

Definition at line 275 of file ThresholdCrossingDetector.cpp.

UINT ThresholdCrossingDetector::getThresholdCrossingMode

(

)

const

Returns

returns the current threshold crossing mode being used, this will be one of the ThresholdCrossingModes enums

Definition at line 287 of file ThresholdCrossingDetector.cpp.

Float ThresholdCrossingDetector::getUpperThreshold

(

)

const

Returns

gets the upper threshold value

Definition at line 315 of file ThresholdCrossingDetector.cpp.

ThresholdCrossingDetector & ThresholdCrossingDetector::operator=

(

const ThresholdCrossingDetector &

rhs

)

Equals Operator. Copies the data from the rhs instance to this instance.

Parameters

rhs	the right hand instance from which the data will be copied to this instance

Returns

returns a reference to this instance

Definition at line 70 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::reset

(

)

This function resets the threshold crossing detector.

Returns

returns true if the threshold crossing detector was reset, false otherwise

Definition at line 249 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::setAnalysisMode

(

const UINT

analysisMode

)

Sets the anlysis mode used to detect threshold crossings. This should be one of the AnalysisModes enums.

Parameters

const

UINT analysisMode: the new analysisMode

Returns

returns true if the parameter was updated, false otherwise

Definition at line 332 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::setDetectionTimeoutMode

(

const UINT

detectionTimeoutMode

)

Sets the detectionTimeoutMode, this controls how the detection algorithm triggers detection timeouts after a threshold crossing has been detected. If the detectionTimeoutMode is TIMEOUT_COUNTER then the detection algorithm will wait for until the searchTimeoutDuration before searching for the next threshold crossing. Alternatively, if the detectionTimeoutMode is HYSTERESIS_THRESHOLD then the detection algorithm will wait for the analysis signal to pass the hysteresisThreshold (regardless of the time this takes) before searching for a new threshold crossing.

Parameters

const

UINT searchTimeoutDuration: the new searchTimeoutDuration

Returns

returns true if the parameter was updated, false otherwise

Definition at line 342 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::setEnableSearch

(

const bool

enableSearch

)

Sets if the algorithm can perform the threshold crossing search. If enableSearch is set to false, then the algorithm will never search for a threshold crossing.

Parameters

const

bool enableSearch: the new enableSearch mode

Returns

returns true if the parameter was updated, false otherwise

Definition at line 327 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::setHysteresisThreshold

(

const Float

hysteresisThreshold

)

Sets the hysteresisThreshold value, this threshold is used to debounce triggers if the detectionTimeoutMode is set to HYSTERESIS_THRESHOLD.

Parameters

hysteresisThreshold

the new hysteresisThreshold

Returns

returns true if the parameter was updated, false otherwise

Definition at line 372 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::setLowerThreshold

(

const Float

lowerThreshold

)

Sets the lowerThreshold value, this lower threshold that must be crossed to trigger a LOWER_THRESHOLD_CROSSING.

Parameters

lowerThreshold

the new lowerThreshold

Returns

returns true if the parameter was updated, false otherwise

Definition at line 362 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::setOffsetFilterSize

(

const UINT

offsetFilterSize

)

Sets the size of the moving average filter used to offset the input data. This is only used if the analysisMode is MOVING_OFFSET_ANALYSIS_MODE.

Parameters

const

UINT offsetFilterSize: the new offsetFilterSize

Returns

returns true if the parameter was updated, false otherwise

Definition at line 352 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::setSearchTimeoutDuration

(

const UINT

searchTimeoutDuration

)

Sets the searchTimeoutDuration, this is the time (in milliseconds) that will be ignored after a threshold crossing has been detected.

Parameters

const

UINT searchTimeoutDuration: the new searchTimeoutDuration in milliseconds

Returns

returns true if the parameter was updated, false otherwise

Definition at line 357 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::setSearchWindowSize

(

const UINT

searchWindowSize

)

Sets the searchWindowSize. This is the number of samples the algorithm will search for a second threshold crossing after the first threshold crossing has been found (in the UPPER_THEN_LOWER_THRESHOLD_CROSSING or LOWER_THEN_UPPER_THRESHOLD_CROSSING modes).

Parameters

const

UINT searchWindowSize: the new searchWindowSize

Returns

returns true if the parameter was updated, false otherwise

Definition at line 347 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::setThresholdCrossingMode

(

const UINT

thresholdCrossingMode

)

Sets the threshold crossing mode used to detect threshold crossings. This should be one of the ThresholdCrossingModes enums.

Parameters

const

UINT thresholdCrossingMode: the new thresholdCrossingMode

Returns

returns true if the parameter was updated, false otherwise

Definition at line 337 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::setUpperThreshold

(

const Float

upperThreshold

)

Sets the upperThreshold value, this upper threshold that must be crossed to trigger a UPPER_THRESHOLD_CROSSING.

Parameters

upperThreshold

the new upperThreshold

Returns

returns true if the parameter was updated, false otherwise

Definition at line 367 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::triggerSearchTimeout

(

)

This function triggers a search timeout (i.e. the algorithm will stop searching for the next N samples, where N = searchTimeoutDuration).

Returns

returns true if the search timeout was triggered, false otherwise

Definition at line 269 of file ThresholdCrossingDetector.cpp.

bool ThresholdCrossingDetector::update

(

const Float

x

)

This is the main update interface, you should call this every time you get a new sample from your sensor.

Parameters

x	the new value that will be pushed through the threshold crossing algorithm

Returns

returns true if a threshold crossing was detected, false otherwise

Definition at line 92 of file ThresholdCrossingDetector.cpp.

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

• ThresholdCrossingDetector.h
• ThresholdCrossingDetector.cpp