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- /*-----------------------------------------------------------------------------
- * 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_init_q15.c
- *
- * Description: Q15 NLMS initialization function.
- *
- * 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"
- #include "arm_common_tables.h"
-
- /**
- * @addtogroup LMS_NORM
- * @{
- */
-
- /**
- * @brief Initialization function for Q15 normalized LMS filter.
- * @param[in] *S points to an instance of the Q15 normalized LMS filter structure.
- * @param[in] numTaps number of filter coefficients.
- * @param[in] *pCoeffs points to coefficient buffer.
- * @param[in] *pState points to state buffer.
- * @param[in] mu step size that controls filter coefficient updates.
- * @param[in] blockSize number of samples to process.
- * @param[in] postShift bit shift applied to coefficients.
- * @return none.
- *
- * <b>Description:</b>
- * \par
- * <code>pCoeffs</code> points to the array of filter coefficients stored in time reversed order:
- * <pre>
- * {b[numTaps-1], b[numTaps-2], b[N-2], ..., b[1], b[0]}
- * </pre>
- * The initial filter coefficients serve as a starting point for the adaptive filter.
- * <code>pState</code> points to the array of state variables and size of array is
- * <code>numTaps+blockSize-1</code> samples, where <code>blockSize</code> is the number of input samples processed
- * by each call to <code>arm_lms_norm_q15()</code>.
- */
-
- void arm_lms_norm_init_q15(
- arm_lms_norm_instance_q15 * S,
- uint16_t numTaps,
- q15_t * pCoeffs,
- q15_t * pState,
- q15_t mu,
- uint32_t blockSize,
- uint8_t postShift)
- {
- /* Assign filter taps */
- S->numTaps = numTaps;
-
- /* Assign coefficient pointer */
- S->pCoeffs = pCoeffs;
-
- /* Clear state buffer and size is always blockSize + numTaps - 1 */
- memset(pState, 0, (numTaps + (blockSize - 1u)) * sizeof(q15_t));
-
- /* Assign post Shift value applied to coefficients */
- S->postShift = postShift;
-
- /* Assign state pointer */
- S->pState = pState;
-
- /* Assign Step size value */
- S->mu = mu;
-
- /* Initialize reciprocal pointer table */
- S->recipTable = (q15_t *) armRecipTableQ15;
-
- /* Initialise Energy to zero */
- S->energy = 0;
-
- /* Initialise x0 to zero */
- S->x0 = 0;
-
- }
-
- /**
- * @} end of LMS_NORM group
- */
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