/* ---------------------------------------------------------------------- * Project: CMSIS DSP Library * Title: arm_iir_lattice_init_f32.c * Description: Floating-point IIR lattice filter initialization function * * $Date: 27. January 2017 * $Revision: V.1.5.1 * * Target Processor: Cortex-M cores * -------------------------------------------------------------------- */ /* * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved. * * SPDX-License-Identifier: Apache-2.0 * * Licensed under the Apache License, Version 2.0 (the License); you may * not use this file except in compliance with the License. * You may obtain a copy of the License at * * www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an AS IS BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #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 */