| /* ---------------------------------------------------------------------- |
| * Project: CMSIS DSP Library |
| * Title: arm_iir_lattice_init_f32.c |
| * Description: Floating-point IIR lattice filter initialization function |
| * |
| * $Date: 18. March 2019 |
| * $Revision: V1.6.0 |
| * |
| * Target Processor: Cortex-M cores |
| * -------------------------------------------------------------------- */ |
| /* |
| * Copyright (C) 2010-2019 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 reflection coefficient buffer. The array is of length numStages |
| @param[in] pvCoeffs points to ladder coefficient buffer. The array is of length numStages+1 |
| @param[in] pState points to 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 |
| */ |