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Diffstat (limited to 'tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/TransformFunctions/arm_bitreversal.c')
| -rw-r--r-- | tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/TransformFunctions/arm_bitreversal.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/TransformFunctions/arm_bitreversal.c b/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/TransformFunctions/arm_bitreversal.c new file mode 100644 index 0000000000..7e1795db31 --- /dev/null +++ b/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/TransformFunctions/arm_bitreversal.c @@ -0,0 +1,242 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010-2013 ARM Limited. All rights reserved. +* +* $Date: 17. January 2013 +* $Revision: V1.4.1 +* +* Project: CMSIS DSP Library +* Title: arm_bitreversal.c +* +* Description: This file has common tables like Bitreverse, reciprocal etc which are used across different functions +* +* 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" + +/* +* @brief In-place bit reversal function. +* @param[in, out] *pSrc points to the in-place buffer of floating-point data type. +* @param[in] fftSize length of the FFT. +* @param[in] bitRevFactor bit reversal modifier that supports different size FFTs with the same bit reversal table. +* @param[in] *pBitRevTab points to the bit reversal table. +* @return none. +*/ + +void arm_bitreversal_f32( +float32_t * pSrc, +uint16_t fftSize, +uint16_t bitRevFactor, +uint16_t * pBitRevTab) +{ + uint16_t fftLenBy2, fftLenBy2p1; + uint16_t i, j; + float32_t in; + + /* Initializations */ + j = 0u; + fftLenBy2 = fftSize >> 1u; + fftLenBy2p1 = (fftSize >> 1u) + 1u; + + /* Bit Reversal Implementation */ + for (i = 0u; i <= (fftLenBy2 - 2u); i += 2u) + { + if(i < j) + { + /* pSrc[i] <-> pSrc[j]; */ + in = pSrc[2u * i]; + pSrc[2u * i] = pSrc[2u * j]; + pSrc[2u * j] = in; + + /* pSrc[i+1u] <-> pSrc[j+1u] */ + in = pSrc[(2u * i) + 1u]; + pSrc[(2u * i) + 1u] = pSrc[(2u * j) + 1u]; + pSrc[(2u * j) + 1u] = in; + + /* pSrc[i+fftLenBy2p1] <-> pSrc[j+fftLenBy2p1] */ + in = pSrc[2u * (i + fftLenBy2p1)]; + pSrc[2u * (i + fftLenBy2p1)] = pSrc[2u * (j + fftLenBy2p1)]; + pSrc[2u * (j + fftLenBy2p1)] = in; + + /* pSrc[i+fftLenBy2p1+1u] <-> pSrc[j+fftLenBy2p1+1u] */ + in = pSrc[(2u * (i + fftLenBy2p1)) + 1u]; + pSrc[(2u * (i + fftLenBy2p1)) + 1u] = + pSrc[(2u * (j + fftLenBy2p1)) + 1u]; + pSrc[(2u * (j + fftLenBy2p1)) + 1u] = in; + + } + + /* pSrc[i+1u] <-> pSrc[j+1u] */ + in = pSrc[2u * (i + 1u)]; + pSrc[2u * (i + 1u)] = pSrc[2u * (j + fftLenBy2)]; + pSrc[2u * (j + fftLenBy2)] = in; + + /* pSrc[i+2u] <-> pSrc[j+2u] */ + in = pSrc[(2u * (i + 1u)) + 1u]; + pSrc[(2u * (i + 1u)) + 1u] = pSrc[(2u * (j + fftLenBy2)) + 1u]; + pSrc[(2u * (j + fftLenBy2)) + 1u] = in; + + /* Reading the index for the bit reversal */ + j = *pBitRevTab; + + /* Updating the bit reversal index depending on the fft length */ + pBitRevTab += bitRevFactor; + } +} + + + +/* +* @brief In-place bit reversal function. +* @param[in, out] *pSrc points to the in-place buffer of Q31 data type. +* @param[in] fftLen length of the FFT. +* @param[in] bitRevFactor bit reversal modifier that supports different size FFTs with the same bit reversal table +* @param[in] *pBitRevTab points to bit reversal table. +* @return none. +*/ + +void arm_bitreversal_q31( +q31_t * pSrc, +uint32_t fftLen, +uint16_t bitRevFactor, +uint16_t * pBitRevTable) +{ + uint32_t fftLenBy2, fftLenBy2p1, i, j; + q31_t in; + + /* Initializations */ + j = 0u; + fftLenBy2 = fftLen / 2u; + fftLenBy2p1 = (fftLen / 2u) + 1u; + + /* Bit Reversal Implementation */ + for (i = 0u; i <= (fftLenBy2 - 2u); i += 2u) + { + if(i < j) + { + /* pSrc[i] <-> pSrc[j]; */ + in = pSrc[2u * i]; + pSrc[2u * i] = pSrc[2u * j]; + pSrc[2u * j] = in; + + /* pSrc[i+1u] <-> pSrc[j+1u] */ + in = pSrc[(2u * i) + 1u]; + pSrc[(2u * i) + 1u] = pSrc[(2u * j) + 1u]; + pSrc[(2u * j) + 1u] = in; + + /* pSrc[i+fftLenBy2p1] <-> pSrc[j+fftLenBy2p1] */ + in = pSrc[2u * (i + fftLenBy2p1)]; + pSrc[2u * (i + fftLenBy2p1)] = pSrc[2u * (j + fftLenBy2p1)]; + pSrc[2u * (j + fftLenBy2p1)] = in; + + /* pSrc[i+fftLenBy2p1+1u] <-> pSrc[j+fftLenBy2p1+1u] */ + in = pSrc[(2u * (i + fftLenBy2p1)) + 1u]; + pSrc[(2u * (i + fftLenBy2p1)) + 1u] = + pSrc[(2u * (j + fftLenBy2p1)) + 1u]; + pSrc[(2u * (j + fftLenBy2p1)) + 1u] = in; + + } + + /* pSrc[i+1u] <-> pSrc[j+1u] */ + in = pSrc[2u * (i + 1u)]; + pSrc[2u * (i + 1u)] = pSrc[2u * (j + fftLenBy2)]; + pSrc[2u * (j + fftLenBy2)] = in; + + /* pSrc[i+2u] <-> pSrc[j+2u] */ + in = pSrc[(2u * (i + 1u)) + 1u]; + pSrc[(2u * (i + 1u)) + 1u] = pSrc[(2u * (j + fftLenBy2)) + 1u]; + pSrc[(2u * (j + fftLenBy2)) + 1u] = in; + + /* Reading the index for the bit reversal */ + j = *pBitRevTable; + + /* Updating the bit reversal index depending on the fft length */ + pBitRevTable += bitRevFactor; + } +} + + + +/* + * @brief In-place bit reversal function. + * @param[in, out] *pSrc points to the in-place buffer of Q15 data type. + * @param[in] fftLen length of the FFT. + * @param[in] bitRevFactor bit reversal modifier that supports different size FFTs with the same bit reversal table + * @param[in] *pBitRevTab points to bit reversal table. + * @return none. +*/ + +void arm_bitreversal_q15( +q15_t * pSrc16, +uint32_t fftLen, +uint16_t bitRevFactor, +uint16_t * pBitRevTab) +{ + q31_t *pSrc = (q31_t *) pSrc16; + q31_t in; + uint32_t fftLenBy2, fftLenBy2p1; + uint32_t i, j; + + /* Initializations */ + j = 0u; + fftLenBy2 = fftLen / 2u; + fftLenBy2p1 = (fftLen / 2u) + 1u; + + /* Bit Reversal Implementation */ + for (i = 0u; i <= (fftLenBy2 - 2u); i += 2u) + { + if(i < j) + { + /* pSrc[i] <-> pSrc[j]; */ + /* pSrc[i+1u] <-> pSrc[j+1u] */ + in = pSrc[i]; + pSrc[i] = pSrc[j]; + pSrc[j] = in; + + /* pSrc[i + fftLenBy2p1] <-> pSrc[j + fftLenBy2p1]; */ + /* pSrc[i + fftLenBy2p1+1u] <-> pSrc[j + fftLenBy2p1+1u] */ + in = pSrc[i + fftLenBy2p1]; + pSrc[i + fftLenBy2p1] = pSrc[j + fftLenBy2p1]; + pSrc[j + fftLenBy2p1] = in; + } + + /* pSrc[i+1u] <-> pSrc[j+fftLenBy2]; */ + /* pSrc[i+2] <-> pSrc[j+fftLenBy2+1u] */ + in = pSrc[i + 1u]; + pSrc[i + 1u] = pSrc[j + fftLenBy2]; + pSrc[j + fftLenBy2] = in; + + /* Reading the index for the bit reversal */ + j = *pBitRevTab; + + /* Updating the bit reversal index depending on the fft length */ + pBitRevTab += bitRevFactor; + } +} |