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| author | joshua <joshua@joshuayun.com> | 2023-12-30 23:54:31 -0500 |
|---|---|---|
| committer | joshua <joshua@joshuayun.com> | 2023-12-30 23:54:31 -0500 |
| commit | 86608c6770cf08c138a2bdab5855072f64be09ef (patch) | |
| tree | 494a61b3ef37e76f9235a0d10f5c93d97290a35f /Drivers/CMSIS/DSP/Source/TransformFunctions/arm_bitreversal.c | |
| download | sdr-software-master.tar.gz | |
Diffstat (limited to 'Drivers/CMSIS/DSP/Source/TransformFunctions/arm_bitreversal.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/TransformFunctions/arm_bitreversal.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_bitreversal.c b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_bitreversal.c new file mode 100644 index 0000000..de95c59 --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_bitreversal.c @@ -0,0 +1,229 @@ +/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_bitreversal.c
+ * Description: Bitreversal functions
+ *
+ * $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"
+#include "arm_common_tables.h"
+
+/**
+ @brief In-place floating-point bit reversal function.
+ @param[in,out] pSrc points to in-place floating-point data buffer
+ @param[in] fftSize length of 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_f32(
+ float32_t * pSrc,
+ uint16_t fftSize,
+ uint16_t bitRevFactor,
+ const 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 Q31 bit reversal function.
+ @param[in,out] pSrc points to in-place Q31 data buffer.
+ @param[in] fftLen length of 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,
+ const uint16_t * pBitRevTab)
+{
+ 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 = *pBitRevTab;
+
+ /* Updating the bit reversal index depending on the fft length */
+ pBitRevTab += bitRevFactor;
+ }
+}
+
+
+
+/**
+ @brief In-place Q15 bit reversal function.
+ @param[in,out] pSrc16 points to in-place Q15 data buffer
+ @param[in] fftLen length of 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,
+ const 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;
+ }
+}
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