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Diffstat (limited to 'tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/FilteringFunctions/arm_fir_interpolate_init_f32.c')
| -rw-r--r-- | tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/FilteringFunctions/arm_fir_interpolate_init_f32.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/FilteringFunctions/arm_fir_interpolate_init_f32.c b/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/FilteringFunctions/arm_fir_interpolate_init_f32.c new file mode 100644 index 0000000000..ffcb7e8cf4 --- /dev/null +++ b/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/FilteringFunctions/arm_fir_interpolate_init_f32.c @@ -0,0 +1,121 @@ +/*----------------------------------------------------------------------------- +* Copyright (C) 2010-2013 ARM Limited. All rights reserved. +* +* $Date: 17. January 2013 +* $Revision: V1.4.1 +* +* Project: CMSIS DSP Library +* Title: arm_fir_interpolate_init_f32.c +* +* Description: Floating-point FIR interpolator 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 FIR_Interpolate + * @{ + */ + +/** + * @brief Initialization function for the floating-point FIR interpolator. + * @param[in,out] *S points to an instance of the floating-point FIR interpolator structure. + * @param[in] L upsample factor. + * @param[in] numTaps number of filter coefficients in the filter. + * @param[in] *pCoeffs points to the filter coefficient buffer. + * @param[in] *pState points to the state buffer. + * @param[in] blockSize number of input samples to process per call. + * @return The function returns ARM_MATH_SUCCESS if initialization was successful or ARM_MATH_LENGTH_ERROR if + * the filter length <code>numTaps</code> is not a multiple of the interpolation factor <code>L</code>. + * + * <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[numTaps-2], ..., b[1], b[0]} + * </pre> + * The length of the filter <code>numTaps</code> must be a multiple of the interpolation factor <code>L</code>. + * \par + * <code>pState</code> points to the array of state variables. + * <code>pState</code> is of length <code>(numTaps/L)+blockSize-1</code> words + * where <code>blockSize</code> is the number of input samples processed by each call to <code>arm_fir_interpolate_f32()</code>. + */ + +arm_status arm_fir_interpolate_init_f32( + arm_fir_interpolate_instance_f32 * S, + uint8_t L, + uint16_t numTaps, + float32_t * pCoeffs, + float32_t * pState, + uint32_t blockSize) +{ + arm_status status; + + /* The filter length must be a multiple of the interpolation factor */ + if((numTaps % L) != 0u) + { + /* Set status as ARM_MATH_LENGTH_ERROR */ + status = ARM_MATH_LENGTH_ERROR; + } + else + { + + /* Assign coefficient pointer */ + S->pCoeffs = pCoeffs; + + /* Assign Interpolation factor */ + S->L = L; + + /* Assign polyPhaseLength */ + S->phaseLength = numTaps / L; + + /* Clear state buffer and size of state array is always phaseLength + blockSize - 1 */ + memset(pState, 0, + (blockSize + + ((uint32_t) S->phaseLength - 1u)) * sizeof(float32_t)); + + /* Assign state pointer */ + S->pState = pState; + + status = ARM_MATH_SUCCESS; + } + + return (status); + +} + + /** + * @} end of FIR_Interpolate group + */ |