/*----------------------------------------------------------------------------- * Copyright (C) 2010-2013 ARM Limited. All rights reserved. * * $Date: 17. January 2013 * $Revision: V1.4.1 * * Project: CMSIS DSP Library * Title: arm_iir_lattice_init_f32.c * * Description: Floating-point IIR lattice filter 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" /** * @ingroup groupFilters */ /** * @addtogroup IIR_Lattice * @{ */ /** * @brief Initialization function for the floating-point IIR lattice filter. * @param[in] *S points to an instance of the floating-point IIR lattice structure. * @param[in] numStages number of stages in the filter. * @param[in] *pkCoeffs points to the reflection coefficient buffer. The array is of length numStages. * @param[in] *pvCoeffs points to the ladder coefficient buffer. The array is of length numStages+1. * @param[in] *pState points to the state buffer. The array is of length numStages+blockSize. * @param[in] blockSize number of samples to process. * @return none. */ void arm_iir_lattice_init_f32( arm_iir_lattice_instance_f32 * S, uint16_t numStages, float32_t * pkCoeffs, float32_t * pvCoeffs, float32_t * pState, uint32_t blockSize) { /* Assign filter taps */ S->numStages = numStages; /* Assign reflection coefficient pointer */ S->pkCoeffs = pkCoeffs; /* Assign ladder coefficient pointer */ S->pvCoeffs = pvCoeffs; /* Clear state buffer and size is always blockSize + numStages */ memset(pState, 0, (numStages + blockSize) * sizeof(float32_t)); /* Assign state pointer */ S->pState = pState; } /** * @} end of IIR_Lattice group */