+++ /dev/null
-/* ----------------------------------------------------------------------
-* Copyright (C) 2010-2013 ARM Limited. All rights reserved.
-*
-* $Date: 17. January 2013
-* $Revision: V1.4.1
-*
-* Project: CMSIS DSP Library
-* Title: arm_lms_norm_q31.c
-*
-* Description: Processing function for the Q31 NLMS filter.
-*
-* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
-*
-* Redistribution and use in source and binary forms, with or without
-* modification, are permitted provided that the following conditions
-* are met:
-* - Redistributions of source code must retain the above copyright
-* notice, this list of conditions and the following disclaimer.
-* - Redistributions in binary form must reproduce the above copyright
-* notice, this list of conditions and the following disclaimer in
-* the documentation and/or other materials provided with the
-* distribution.
-* - Neither the name of ARM LIMITED nor the names of its contributors
-* may be used to endorse or promote products derived from this
-* software without specific prior written permission.
-*
-* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
-* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
-* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
-* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
-* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
-* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
-* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
-* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-* POSSIBILITY OF SUCH DAMAGE.
-* -------------------------------------------------------------------- */
-
-#include "arm_math.h"
-
-/**
- * @ingroup groupFilters
- */
-
-/**
- * @addtogroup LMS_NORM
- * @{
- */
-
-/**
-* @brief Processing function for Q31 normalized LMS filter.
-* @param[in] *S points to an instance of the Q31 normalized LMS filter structure.
-* @param[in] *pSrc points to the block of input data.
-* @param[in] *pRef points to the block of reference data.
-* @param[out] *pOut points to the block of output data.
-* @param[out] *pErr points to the block of error data.
-* @param[in] blockSize number of samples to process.
-* @return none.
-*
-* <b>Scaling and Overflow Behavior:</b>
-* \par
-* The function is implemented using an internal 64-bit accumulator.
-* The accumulator has a 2.62 format and maintains full precision of the intermediate
-* multiplication results but provides only a single guard bit.
-* Thus, if the accumulator result overflows it wraps around rather than clip.
-* In order to avoid overflows completely the input signal must be scaled down by
-* log2(numTaps) bits. The reference signal should not be scaled down.
-* After all multiply-accumulates are performed, the 2.62 accumulator is shifted
-* and saturated to 1.31 format to yield the final result.
-* The output signal and error signal are in 1.31 format.
-*
-* \par
-* In this filter, filter coefficients are updated for each sample and the
-* updation of filter cofficients are saturted.
-*
-*/
-
-void arm_lms_norm_q31(
- arm_lms_norm_instance_q31 * S,
- q31_t * pSrc,
- q31_t * pRef,
- q31_t * pOut,
- q31_t * pErr,
- uint32_t blockSize)
-{
- q31_t *pState = S->pState; /* State pointer */
- q31_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
- q31_t *pStateCurnt; /* Points to the current sample of the state */
- q31_t *px, *pb; /* Temporary pointers for state and coefficient buffers */
- q31_t mu = S->mu; /* Adaptive factor */
- uint32_t numTaps = S->numTaps; /* Number of filter coefficients in the filter */
- uint32_t tapCnt, blkCnt; /* Loop counters */
- q63_t energy; /* Energy of the input */
- q63_t acc; /* Accumulator */
- q31_t e = 0, d = 0; /* error, reference data sample */
- q31_t w = 0, in; /* weight factor and state */
- q31_t x0; /* temporary variable to hold input sample */
-// uint32_t shift = 32u - ((uint32_t) S->postShift + 1u); /* Shift to be applied to the output */
- q31_t errorXmu, oneByEnergy; /* Temporary variables to store error and mu product and reciprocal of energy */
- q31_t postShift; /* Post shift to be applied to weight after reciprocal calculation */
- q31_t coef; /* Temporary variable for coef */
- q31_t acc_l, acc_h; /* temporary input */
- uint32_t uShift = ((uint32_t) S->postShift + 1u);
- uint32_t lShift = 32u - uShift; /* Shift to be applied to the output */
-
- energy = S->energy;
- x0 = S->x0;
-
- /* S->pState points to buffer which contains previous frame (numTaps - 1) samples */
- /* pStateCurnt points to the location where the new input data should be written */
- pStateCurnt = &(S->pState[(numTaps - 1u)]);
-
- /* Loop over blockSize number of values */
- blkCnt = blockSize;
-
-
-#ifndef ARM_MATH_CM0_FAMILY
-
- /* Run the below code for Cortex-M4 and Cortex-M3 */
-
- while(blkCnt > 0u)
- {
-
- /* Copy the new input sample into the state buffer */
- *pStateCurnt++ = *pSrc;
-
- /* Initialize pState pointer */
- px = pState;
-
- /* Initialize coeff pointer */
- pb = (pCoeffs);
-
- /* Read the sample from input buffer */
- in = *pSrc++;
-
- /* Update the energy calculation */
- energy = (q31_t) ((((q63_t) energy << 32) -
- (((q63_t) x0 * x0) << 1)) >> 32);
- energy = (q31_t) (((((q63_t) in * in) << 1) + (energy << 32)) >> 32);
-
- /* Set the accumulator to zero */
- acc = 0;
-
- /* Loop unrolling. Process 4 taps at a time. */
- tapCnt = numTaps >> 2;
-
- while(tapCnt > 0u)
- {
- /* Perform the multiply-accumulate */
- acc += ((q63_t) (*px++)) * (*pb++);
- acc += ((q63_t) (*px++)) * (*pb++);
- acc += ((q63_t) (*px++)) * (*pb++);
- acc += ((q63_t) (*px++)) * (*pb++);
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* If the filter length is not a multiple of 4, compute the remaining filter taps */
- tapCnt = numTaps % 0x4u;
-
- while(tapCnt > 0u)
- {
- /* Perform the multiply-accumulate */
- acc += ((q63_t) (*px++)) * (*pb++);
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* Converting the result to 1.31 format */
- /* Calc lower part of acc */
- acc_l = acc & 0xffffffff;
-
- /* Calc upper part of acc */
- acc_h = (acc >> 32) & 0xffffffff;
-
- acc = (uint32_t) acc_l >> lShift | acc_h << uShift;
-
- /* Store the result from accumulator into the destination buffer. */
- *pOut++ = (q31_t) acc;
-
- /* Compute and store error */
- d = *pRef++;
- e = d - (q31_t) acc;
- *pErr++ = e;
-
- /* Calculates the reciprocal of energy */
- postShift = arm_recip_q31(energy + DELTA_Q31,
- &oneByEnergy, &S->recipTable[0]);
-
- /* Calculation of product of (e * mu) */
- errorXmu = (q31_t) (((q63_t) e * mu) >> 31);
-
- /* Weighting factor for the normalized version */
- w = clip_q63_to_q31(((q63_t) errorXmu * oneByEnergy) >> (31 - postShift));
-
- /* Initialize pState pointer */
- px = pState;
-
- /* Initialize coeff pointer */
- pb = (pCoeffs);
-
- /* Loop unrolling. Process 4 taps at a time. */
- tapCnt = numTaps >> 2;
-
- /* Update filter coefficients */
- while(tapCnt > 0u)
- {
- /* Perform the multiply-accumulate */
-
- /* coef is in 2.30 format */
- coef = (q31_t) (((q63_t) w * (*px++)) >> (32));
- /* get coef in 1.31 format by left shifting */
- *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
- /* update coefficient buffer to next coefficient */
- pb++;
-
- coef = (q31_t) (((q63_t) w * (*px++)) >> (32));
- *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
- pb++;
-
- coef = (q31_t) (((q63_t) w * (*px++)) >> (32));
- *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
- pb++;
-
- coef = (q31_t) (((q63_t) w * (*px++)) >> (32));
- *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
- pb++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* If the filter length is not a multiple of 4, compute the remaining filter taps */
- tapCnt = numTaps % 0x4u;
-
- while(tapCnt > 0u)
- {
- /* Perform the multiply-accumulate */
- coef = (q31_t) (((q63_t) w * (*px++)) >> (32));
- *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
- pb++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* Read the sample from state buffer */
- x0 = *pState;
-
- /* Advance state pointer by 1 for the next sample */
- pState = pState + 1;
-
- /* Decrement the loop counter */
- blkCnt--;
- }
-
- /* Save energy and x0 values for the next frame */
- S->energy = (q31_t) energy;
- S->x0 = x0;
-
- /* Processing is complete. Now copy the last numTaps - 1 samples to the
- satrt of the state buffer. This prepares the state buffer for the
- next function call. */
-
- /* Points to the start of the pState buffer */
- pStateCurnt = S->pState;
-
- /* Loop unrolling for (numTaps - 1u) samples copy */
- tapCnt = (numTaps - 1u) >> 2u;
-
- /* copy data */
- while(tapCnt > 0u)
- {
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* Calculate remaining number of copies */
- tapCnt = (numTaps - 1u) % 0x4u;
-
- /* Copy the remaining q31_t data */
- while(tapCnt > 0u)
- {
- *pStateCurnt++ = *pState++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
-#else
-
- /* Run the below code for Cortex-M0 */
-
- while(blkCnt > 0u)
- {
-
- /* Copy the new input sample into the state buffer */
- *pStateCurnt++ = *pSrc;
-
- /* Initialize pState pointer */
- px = pState;
-
- /* Initialize pCoeffs pointer */
- pb = pCoeffs;
-
- /* Read the sample from input buffer */
- in = *pSrc++;
-
- /* Update the energy calculation */
- energy =
- (q31_t) ((((q63_t) energy << 32) - (((q63_t) x0 * x0) << 1)) >> 32);
- energy = (q31_t) (((((q63_t) in * in) << 1) + (energy << 32)) >> 32);
-
- /* Set the accumulator to zero */
- acc = 0;
-
- /* Loop over numTaps number of values */
- tapCnt = numTaps;
-
- while(tapCnt > 0u)
- {
- /* Perform the multiply-accumulate */
- acc += ((q63_t) (*px++)) * (*pb++);
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* Converting the result to 1.31 format */
- /* Converting the result to 1.31 format */
- /* Calc lower part of acc */
- acc_l = acc & 0xffffffff;
-
- /* Calc upper part of acc */
- acc_h = (acc >> 32) & 0xffffffff;
-
- acc = (uint32_t) acc_l >> lShift | acc_h << uShift;
-
-
- //acc = (q31_t) (acc >> shift);
-
- /* Store the result from accumulator into the destination buffer. */
- *pOut++ = (q31_t) acc;
-
- /* Compute and store error */
- d = *pRef++;
- e = d - (q31_t) acc;
- *pErr++ = e;
-
- /* Calculates the reciprocal of energy */
- postShift =
- arm_recip_q31(energy + DELTA_Q31, &oneByEnergy, &S->recipTable[0]);
-
- /* Calculation of product of (e * mu) */
- errorXmu = (q31_t) (((q63_t) e * mu) >> 31);
-
- /* Weighting factor for the normalized version */
- w = clip_q63_to_q31(((q63_t) errorXmu * oneByEnergy) >> (31 - postShift));
-
- /* Initialize pState pointer */
- px = pState;
-
- /* Initialize coeff pointer */
- pb = (pCoeffs);
-
- /* Loop over numTaps number of values */
- tapCnt = numTaps;
-
- while(tapCnt > 0u)
- {
- /* Perform the multiply-accumulate */
- /* coef is in 2.30 format */
- coef = (q31_t) (((q63_t) w * (*px++)) >> (32));
- /* get coef in 1.31 format by left shifting */
- *pb = clip_q63_to_q31((q63_t) * pb + (coef << 1u));
- /* update coefficient buffer to next coefficient */
- pb++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* Read the sample from state buffer */
- x0 = *pState;
-
- /* Advance state pointer by 1 for the next sample */
- pState = pState + 1;
-
- /* Decrement the loop counter */
- blkCnt--;
- }
-
- /* Save energy and x0 values for the next frame */
- S->energy = (q31_t) energy;
- S->x0 = x0;
-
- /* Processing is complete. Now copy the last numTaps - 1 samples to the
- start of the state buffer. This prepares the state buffer for the
- next function call. */
-
- /* Points to the start of the pState buffer */
- pStateCurnt = S->pState;
-
- /* Loop for (numTaps - 1u) samples copy */
- tapCnt = (numTaps - 1u);
-
- /* Copy the remaining q31_t data */
- while(tapCnt > 0u)
- {
- *pStateCurnt++ = *pState++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
-#endif /* #ifndef ARM_MATH_CM0_FAMILY */
-
-}
-
-/**
- * @} end of LMS_NORM group
- */
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