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asptDrnlms32f
API Summary
API to create and delete an asptDrnlms32f filters
API to filter through and update an asptDrnlms32f filters
API to retrieve the properties of an asptDrnlms32f filter
API to set the properties of an asptDrnlms32f filter
- DT32S drnlms32fReset(asptDrnlms32f *drnlms)
- DT32S drnlms32fResetDelayLine(asptDrnlms32f *drnlms)
- DT32S drnlms32fResize(asptDrnlms32f *drnlms, DT32S newLength)
- DT32S drnlms32fSetCoef(asptDrnlms32f *drnlms, DT32F *newCoef, DT32S ind, DT32S N, DT32S flip)
- DT32S drnlms32fSetDelayLine(asptDrnlms32f *drnlms, DT32F *newCoef, DT32S ind, DT32S N, DT32S flip)
- drnlms32fSetStepSize( asptDrnlms32f
*drnlms, newStep )
- drnlmsSetReuseNr( asptDrnlms32f
*drnlms, newNr )
Description
Implements the Data Reusing Normalized Least Mean Squares (DRNLMS) adaptive filter algorithm.
Copyright
Copyright (c) DSP ALGORITHMS 2003; all rights reserved.
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drnlms32fInit
DT32S drnlms32fInit (asptDrnlms32f *drnlms,DT32S L, DT32F mu, DT32S R)
Initializes an asptDrnlms32f filter and allocates its necessary storage buffers. - Returns :
-
Error code. On failure, the filterLength member of the filter is set to zero.
- Input Parameters :
- drnlms : asptDrnlms32f filter to be initialized
- L : number of filter coefficients
- mu : step size
- R : number of data reusing cycles; R=0 is the LMS case
- Error Conditions
- ASPT_NO_ERR : Initialization is successful
- ASPT_RANGE_ERR : L/R is not a valid input value
- ASPT_NO_MEM_ERR : could not allocate memory
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drnlms32fInitStatic
DT32S drnlms32fInitStatic(asptDrnlms32f *drnlms,DT32S L, DT32F mu, DT32S R, DT32F *pCof, DT32F *pDat)
Initializes an asptDrnlms32f filter to use pre-allocated memory. - Returns :
-
Error code. On failure, the filterLength member of the filter is set to zero.
- Input Parameters :
- drnlms : asptDrnlms32f filter to be initialized
- L : number of filter coefficients
- mu : step size
- R : number of data reusing cycles; R=0 is the LMS case
- pCof : pointer to a pre-allocated memory block to be used
for the adaptive filter coefficients. At least L memory locations must be available starting at this memory address.
- pDat : pointer to a pre-allocated memory block to be used
for data storage. At least L memory locations must be available starting at this memory address
- Error Conditions
- ASPT_NO_ERR : Initialization is successful
- ASPT_NULL_PTR_ERR : pCof/pDat is a NULL pointer
- ASPT_RANGE_ERR : L/R is not a valid input value
- ASPT_NO_MEM_ERR : could not allocate memory
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drnlms32fFilterUpdate
DT32F drnlms32fFilterUpdate(asptDrnlms32f *drnlms, DT32F inp, DT32F des)
Calculates the filter output and updates the coefficients vector according to the DRNLMS algorithm. - Returns :
-
The filter output sample.
- Input Parameters :
- drnlms : pointer to asptDrnlms32f filter
- inp : new input sample.
- des : new desired sample
- Remarks :
-
The error sample is stored internally and can be retrieved by calling drnlms32fGetLastErrorSample().
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drnlms32fLCFilterUpdate
DT32F drnlms32fLCFilterUpdate(asptDrnlms32f *drnlms, DT32F des)
Calculates the filter output and updates the coefficients vector according to the DRNLMS algorithm for the Linear Combiner filter configuration. Assumes that the delay line is externally updated before calling, therefore does not update the internal delay line. - Returns :
-
The filter output sample.
- Input Parameters :
- drnlms : pointer to asptDrnlms32f filter
- des : new desired sample
- Remarks :
-
The error sample is stored internally and can be retrieved by calling drnlms32fGetLastErrorSample().
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drnlms32fFilterOnly
DT32F drnlms32fFilterOnly(asptDrnlms32f *drnlms, DT32F inp)
Calculates the filter output but does not updates the coefficients. - Returns :
-
The filter output sample.
- Input Parameters :
- drnlms : pointer to asptDrnlms32f filter
- inp : new input sample.
- Remarks :
-
error sample is not calculated.
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drnlms32fLCFilterOnly
DT32F drnlms32fLCFilterOnly(asptDrnlms32f *drnlms)
Calculates the filter output but does not updates the coefficients for the Linear Combiner filter configuration. Assumes that the delay line is externally updated before calling, therefore does not update the internal delay line. - Returns :
-
The filter output sample.
- Input Parameters :
- drnlms : pointer to asptDrnlms32f filter
- Remarks :
-
error sample is not calculated.
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drnlms32fFree
void drnlms32fFree(asptDrnlms32f *drnlms)
Frees the allocated memory for this drnlms filter. - Returns :
- Input Parameters :
- drnlms : pointer to asptDrnlms32f filter
- Remarks :
-
Use this function only with filters created with drnlms32fInit(). Do not use with asptDrnlms32f filters created using drnlms32fInitStatic().
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drnlms32fReset
DT32S drnlms32fReset(asptDrnlms32f *drnlms)
Resets all filter coefficients to zero.- Returns :
- Input Parameters :
- drnlms : pointer to the asptDrnlms32f filter to be reset
- Error Conditions
- ASPT_NO_ERR : success
- ASPT_NULL_PTR_ERR : NULL pointer error
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drnlms32fResetDelayLine
DT32S drnlms32fResetDelayLine(asptDrnlms32f *drnlms)
Resets all internal delay lines to zero.- Returns :
- Input Parameters :
- drnlms : pointer to the asptDrnlms32f filter to be reset
- Error Conditions
- ASPT_NO_ERR : success
- ASPT_NULL_PTR_ERR : NULL pointer error
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drnlms32fGetCoef
DT32S drnlms32fGetCoef(asptDrnlms32f *drnlms, DT32F *buf, DT32S ind, DT32S N, DT32S flip)
Copies N internal filter coefficients starting from coef[ind] to dstBuf. - Returns :
-
On success returns the number of coefficients copied, otherwise the error code (negative int).
- Input Parameters :
- drnlms : pointer to the asptDrnlms32f filter.
- dstBuf : destination buffer.
- ind : index to the first coefficient to be copied.
- N : number of coefficients to be copied.
- flip : if not 0, will flip the coefficients order
- Output Parameters :
- Error Conditions
- ASPT_NULL_PTR_ERR : dstBuf/drnlms->coef is a NULL pointer
- ASPT_RANGE_ERR : ind/N is not a valid input value
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drnlms32fSetCoef
DT32S drnlms32fSetCoef(asptDrnlms32f *drnlms, DT32F *newCoef, DT32S ind, DT32S N, DT32S flip)
Initializes N internal filter coefficients starting from coef[ind] to the contents of newBuf. - Returns :
-
On success returns the number of coefficients initialized, otherwise the error code (negative int).
- Input Parameters :
- drnlms : pointer to the asptDrnlms32f filter to be set.
- newCoef : new coefficients vector.
- ind : index to the first coefficient to be set.
- N : number of coefficients to be set.
- flip : if not 0, will copy the coefficients in reverse order
- Output Parameters :
- Error Conditions
- ASPT_NULL_PTR_ERR : newCoef/drnlms->coef is a NULL pointer
- ASPT_RANGE_ERR : ind/N is not a valid input value
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drnlms32fGetDelayLine
DT32S drnlms32fGetDelayLine(asptDrnlms32f *drnlms, DT32F *buf, DT32S ind, DT32S N, DT32S flip)
Copies N internal delay line samples starting from delayLine[ind] to dstBuf. - Returns :
-
On success returns the number of samples copied, otherwise the error code (negative int).
- Input Parameters :
- drnlms : pointer to asptDrnlms32f filter.
- dstBuf : destination buffer.
- ind : index to the first sample to be copied.
- N : number of samples to be copied.
- flip : if not 0, will flip the samples order.
- Output Parameters :
- Error Conditions
- ASPT_NULL_PTR_ERR : dstBuf/drnlms->delayLine is a NULL pointer
- ASPT_RANGE_ERR : ind/N is not a valid input value
- Remarks :
-
Samples are stored in dstBuf with newest sample at index 0, and oldest at index N-1, when flip == 0.
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drnlms32fSetDelayLine
DT32S drnlms32fSetDelayLine(asptDrnlms32f *drnlms, DT32F *newCoef, DT32S ind, DT32S N, DT32S flip)
Initializes N internal delay line samples starting from delayLine[ind] to the contents of the given array. - Returns :
-
On success returns the number of samples initialized, otherwise the error code (negative int).
- Input Parameters :
- drnlms : pointer to asptDrnlms32f filter.
- newBuf : new data buffer.
- ind : index to the first sample to be copied.
- N : number of samples to be copied.
- flip : if not 0, will flip the samples order.
- Output Parameters :
- drnlms->delayLine is updated
- Error Conditions
- ASPT_NULL_PTR_ERR : newBuf/drnlms->delayLine is a NULL pointer
- ASPT_RANGE_ERR : ind/N is not a valid input value
- Remarks :
-
Samples assumed to be stored in newBuf with newest sample at index 0, and oldest at index N-1, when flip == 0.
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drnlms32fResize
DT32S drnlms32fResize(asptDrnlms32f *drnlms, DT32S newLength)
Resizes an asptDrnlms32f filter keeping as much of the filter state as possible. - Returns :
- Input Parameters :
- drnlms : pointer to the asptDrnlms32f filter to be resized.
- newLen : required new filter length.
- Error Conditions
- ASPT_NO_ERR : Resizing is success
- ASPT_NULL_PTR_ERR : NULL pointer error
- ASPT_RANGE_ERR : newLength is not a valid input value
- ASPT_NO_MEM_ERR : Could not allocate the necessary filter storage
- Remarks :
-
Use this function only with dynamically allocated asptDrnlms32f filters.