API for the qSSmoother library. More...

Data Structures
struct	qSSmoother_LPF1_t
	A 1st order Low-Pass Filter. More...

struct	qSSmoother_LPF2_t
	A 2nd order Low-Pass Filter. More...

struct	qSSmoother_MWM1_t
	A Moving Window Median filter. More...

struct	qSSmoother_MWM2_t
	A Moving Window Median filter. More...

struct	qSSmoother_MOR1_t
	A Moving Outlier Removal filter. More...

struct	qSSmoother_MOR2_t
	A Moving Outlier Removal filter. More...

struct	qSSmoother_GMWF_t
	A Gaussian filter. More...

struct	qSSmoother_EXPW_t
	An Exponential weighting filter. More...

struct	qSSmoother_KLMN_t
	A scalar Kalman filter. More...

struct	qSSmoother_DESF_t
	Double exponential smoothing (Holt’s Method) More...

struct	qSSmoother_ALNF_t
	Adaptive Filter LMS. More...

Enumerations
enum	qSSmoother_Type_t { QSSMOOTHER_TYPE_LPF1 , QSSMOOTHER_TYPE_LPF2 , QSSMOOTHER_TYPE_MWM1 , QSSMOOTHER_TYPE_MWM2 , QSSMOOTHER_TYPE_MOR1 , QSSMOOTHER_TYPE_MOR2 , QSSMOOTHER_TYPE_GMWF , QSSMOOTHER_TYPE_KLMN , QSSMOOTHER_TYPE_EXPW , QSSMOOTHER_TYPE_DESF , QSSMOOTHER_TYPE_ALNF }
	Supported Filters by the qSSmoother library. More...

Functions
int	qSSmoother_IsInitialized (const qSSmootherPtr_t *const s)
	Check if the smoother filter is initialized.

int	qSSmoother_Reset (qSSmootherPtr_t *const s)
	Reset the the smoother filter.

float	qSSmoother_Perform (qSSmootherPtr_t *const s, const float x)
	Perform the smooth operation recursively for the input signal x.

int	qSSmoother_Setup (qSSmootherPtr_t const s, const qSSmoother_Type_t type, const float const param, float *window, const size_t wsize)
	Setup an initialize smoother filter.

Detailed Description

API for the qSSmoother library.

For a brief description of this module, please read Filters for signal smoothing

Enumeration Type Documentation

◆ qSSmoother_Type_t

enum qSSmoother_Type_t

Supported Filters by the qSSmoother library.

Enumerator
QSSMOOTHER_TYPE_LPF1	Low-Pass filter 1st Order
QSSMOOTHER_TYPE_LPF2	Low-Pass filter 2nd Order
QSSMOOTHER_TYPE_MWM1	Moving Window Median filter ( O(n) time )
QSSMOOTHER_TYPE_MWM2	Moving Window Median filter ( O(1) time by using a TDL )
QSSMOOTHER_TYPE_MOR1	Moving Outliers Removal ( O(n) time )
QSSMOOTHER_TYPE_MOR2	Moving Outliers Removal ( O(1) time by using a TDL )
QSSMOOTHER_TYPE_GMWF	Gaussian Filter
QSSMOOTHER_TYPE_KLMN	Kalman Filter
QSSMOOTHER_TYPE_EXPW	Exponential weighting filter
QSSMOOTHER_TYPE_DESF	Double Exponential Smoother
QSSMOOTHER_TYPE_ALNF	Adaptive Noise Cancellation

Function Documentation

◆ qSSmoother_IsInitialized()

int qSSmoother_IsInitialized ( const qSSmootherPtr_t *const s )

Check if the smoother filter is initialized.

Parameters

[in] s A pointer to the signal smoother instance.

Returns: 1 if the smoother has been initialized, otherwise return 0.

◆ qSSmoother_Perform()

float qSSmoother_Perform	(	qSSmootherPtr_t *const	s,
		const float	x )

Perform the smooth operation recursively for the input signal x.

Precondition: Instance must be previously initialized by qSSmoother_Setup()

Parameters

[in]	s	A pointer to the signal smoother instance.
[in]	x	A sample of the input signal.

Returns: The smoothed output.

◆ qSSmoother_Reset()

int qSSmoother_Reset ( qSSmootherPtr_t *const s )

Reset the the smoother filter.

Parameters

[in] s A pointer to the signal smoother instance.

Returns: 1 on success, otherwise return 0.

◆ qSSmoother_Setup()

int qSSmoother_Setup	(	qSSmootherPtr_t *const	s,
		const qSSmoother_Type_t	type,
		const float *const	param,
		float *	window,
		const size_t	wsize )

Setup an initialize smoother filter.

Parameters

[in]	s	A pointer to the signal smoother instance.
[in]	type	The filter type. Use one of the following values:

QSSMOOTHER_TYPE_LPF1
QSSMOOTHER_TYPE_LPF2
QSSMOOTHER_TYPE_MWM1
QSSMOOTHER_TYPE_MWM2
QSSMOOTHER_TYPE_MOR1
QSSMOOTHER_TYPE_MOR2
QSSMOOTHER_TYPE_GMWF
QSSMOOTHER_TYPE_KLMN
QSSMOOTHER_TYPE_EXPW
QSSMOOTHER_TYPE_DESF
QSSMOOTHER_TYPE_ALNF

Parameters

[in] param The smoother parameters. Depends of the type selected:

if QSSMOOTHER_TYPE_LPF1 a pointer to a value between [ 0 < alpha < 1 ]

if QSSMOOTHER_TYPE_LPF2 a pointer to a value between [ 0 < alpha < 1 ]

if QSSMOOTHER_TYPE_MWM1 can be ignored. Pass NULL as argument.

if QSSMOOTHER_TYPE_MWM2 can be ignored. Pass NULL as argument.

if QSSMOOTHER_TYPE_MOR1 a pointer to a value between [ 0 < alpha < 1 ]

if QSSMOOTHER_TYPE_MOR2 a pointer to a value between [ 0 < alpha < 1 ]

if QSSMOOTHER_TYPE_GMWF, an array with two values. The first element with the Standard deviation [ sigma > 0 ]. The second element with the offset of the gaussian center. [ 0 < offset < ( wsize - 1 ) ].

if QSSMOOTHER_TYPE_KLMN, an array with three values. The first element with the initial estimated error covariance. The second element with the process(predict) noise covariance. The third element with the measure noise convariance

if QSSMOOTHER_TYPE_EXPW, a pointer to a value between [ 0 < lambda < 1 ] that represents the forgetting factor.

if QSSMOOTHER_TYPE_DESF, an array with three values. The first element [ 0 < alpha < 1 ] that represents the weight for the level, the second, [ 0 < beta < 1 ] weight for the trend. The third element with the number of step for the forecast, should be an integer value greater or equal to zero.

if QSSMOOTHER_TYPE_ALNF, an array with two values. The first element with learning rate [ 0 < alpha < 1 ]. The second element with the momentum [ 0 < mu < 1 ].

Parameters

[in] window The filter window and coefficients. Depends of the type selected:

if QSSMOOTHER_TYPE_LPF1, can be ignored. Pass NULL as argument.

if QSSMOOTHER_TYPE_LPF2, can be ignored. Pass NULL as argument.

if QSSMOOTHER_TYPE_MWM1, An array of wsize elements.

if QSSMOOTHER_TYPE_MWM2, An array of wsize elements.

if QSSMOOTHER_TYPE_MOR1, An array of wsize elements.

if QSSMOOTHER_TYPE_MOR2, An array of wsize elements.

if QSSMOOTHER_TYPE_GMWF, An array of 2* wsize to hold both, the window and the gaussian kernel coefficients.

if QSSMOOTHER_TYPE_KLMN, can be ignored. Pass NULL as argument.

if QSSMOOTHER_TYPE_EXPW, can be ignored. Pass NULL as argument.

if QSSMOOTHER_TYPE_DESF, can be ignored. Pass NULL as argument.

if QSSMOOTHER_TYPE_ALNF, An array of 2* wsize elements when momentum is set to zero, otherwise an array of 3* wsize elements.

Parameters

[in] wsize If used, the number of elements in window, otherwise pass 0uL as argument.

Returns: 1 on success, otherwise return 0.

Data Structures

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

◆ qSSmoother_Type_t

Function Documentation

◆ qSSmoother_IsInitialized()

◆ qSSmoother_Perform()

◆ qSSmoother_Reset()

◆ qSSmoother_Setup()