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Diffstat (limited to 'platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_rfft_fast_init_f32.c')
| -rw-r--r-- | platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_rfft_fast_init_f32.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_rfft_fast_init_f32.c b/platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_rfft_fast_init_f32.c new file mode 100644 index 0000000..a2da321 --- /dev/null +++ b/platform/CMSIS/DSP_Lib/Source/TransformFunctions/arm_rfft_fast_init_f32.c @@ -0,0 +1,149 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010-2014 ARM Limited. All rights reserved. +* +* $Date: 31. July 2014 +* $Revision: V1.4.4 +* +* Project: CMSIS DSP Library +* Title: arm_cfft_init_f32.c +* +* Description: Split Radix Decimation in Frequency CFFT Floating point processing 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" + +/** + * @ingroup groupTransforms + */ + +/** + * @addtogroup RealFFT + * @{ + */ + +/** +* @brief Initialization function for the floating-point real FFT. +* @param[in,out] *S points to an arm_rfft_fast_instance_f32 structure. +* @param[in] fftLen length of the Real Sequence. +* @return The function returns ARM_MATH_SUCCESS if initialization is successful or ARM_MATH_ARGUMENT_ERROR if <code>fftLen</code> is not a supported value. +* +* \par Description: +* \par +* The parameter <code>ifftFlag</code> controls whether a forward or inverse transform is computed. +* Set(=1) ifftFlag for calculation of CIFFT otherwise RFFT is calculated +* \par +* The parameter <code>bitReverseFlag</code> controls whether output is in normal order or bit reversed order. +* Set(=1) bitReverseFlag for output to be in normal order otherwise output is in bit reversed order. +* \par +* The parameter <code>fftLen</code> Specifies length of RFFT/CIFFT process. Supported FFT Lengths are 16, 32, 64, 128, 256, 512, 1024, 2048, 4096. +* \par +* This Function also initializes Twiddle factor table pointer and Bit reversal table pointer. +*/ +arm_status arm_rfft_fast_init_f32( + arm_rfft_fast_instance_f32 * S, + uint16_t fftLen) +{ + arm_cfft_instance_f32 * Sint; + /* Initialise the default arm status */ + arm_status status = ARM_MATH_SUCCESS; + /* Initialise the FFT length */ + Sint = &(S->Sint); + Sint->fftLen = fftLen/2; + S->fftLenRFFT = fftLen; + + /* Initializations of structure parameters depending on the FFT length */ + switch (Sint->fftLen) + { + case 2048u: + /* Initializations of structure parameters for 2048 point FFT */ + /* Initialise the bit reversal table length */ + Sint->bitRevLength = ARMBITREVINDEXTABLE2048_TABLE_LENGTH; + /* Initialise the bit reversal table pointer */ + Sint->pBitRevTable = (uint16_t *)armBitRevIndexTable2048; + /* Initialise the Twiddle coefficient pointers */ + Sint->pTwiddle = (float32_t *) twiddleCoef_2048; + S->pTwiddleRFFT = (float32_t *) twiddleCoef_rfft_4096; + break; + case 1024u: + Sint->bitRevLength = ARMBITREVINDEXTABLE1024_TABLE_LENGTH; + Sint->pBitRevTable = (uint16_t *)armBitRevIndexTable1024; + Sint->pTwiddle = (float32_t *) twiddleCoef_1024; + S->pTwiddleRFFT = (float32_t *) twiddleCoef_rfft_2048; + break; + case 512u: + Sint->bitRevLength = ARMBITREVINDEXTABLE_512_TABLE_LENGTH; + Sint->pBitRevTable = (uint16_t *)armBitRevIndexTable512; + Sint->pTwiddle = (float32_t *) twiddleCoef_512; + S->pTwiddleRFFT = (float32_t *) twiddleCoef_rfft_1024; + break; + case 256u: + Sint->bitRevLength = ARMBITREVINDEXTABLE_256_TABLE_LENGTH; + Sint->pBitRevTable = (uint16_t *)armBitRevIndexTable256; + Sint->pTwiddle = (float32_t *) twiddleCoef_256; + S->pTwiddleRFFT = (float32_t *) twiddleCoef_rfft_512; + break; + case 128u: + Sint->bitRevLength = ARMBITREVINDEXTABLE_128_TABLE_LENGTH; + Sint->pBitRevTable = (uint16_t *)armBitRevIndexTable128; + Sint->pTwiddle = (float32_t *) twiddleCoef_128; + S->pTwiddleRFFT = (float32_t *) twiddleCoef_rfft_256; + break; + case 64u: + Sint->bitRevLength = ARMBITREVINDEXTABLE__64_TABLE_LENGTH; + Sint->pBitRevTable = (uint16_t *)armBitRevIndexTable64; + Sint->pTwiddle = (float32_t *) twiddleCoef_64; + S->pTwiddleRFFT = (float32_t *) twiddleCoef_rfft_128; + break; + case 32u: + Sint->bitRevLength = ARMBITREVINDEXTABLE__32_TABLE_LENGTH; + Sint->pBitRevTable = (uint16_t *)armBitRevIndexTable32; + Sint->pTwiddle = (float32_t *) twiddleCoef_32; + S->pTwiddleRFFT = (float32_t *) twiddleCoef_rfft_64; + break; + case 16u: + Sint->bitRevLength = ARMBITREVINDEXTABLE__16_TABLE_LENGTH; + Sint->pBitRevTable = (uint16_t *)armBitRevIndexTable16; + Sint->pTwiddle = (float32_t *) twiddleCoef_16; + S->pTwiddleRFFT = (float32_t *) twiddleCoef_rfft_32; + break; + default: + /* Reporting argument error if fftSize is not valid value */ + status = ARM_MATH_ARGUMENT_ERROR; + break; + } + + return (status); +} + +/** + * @} end of RealFFT group + */ |