| /* ---------------------------------------------------------------------- |
| * Project: CMSIS DSP Library |
| * Title: arm_cmplx_mag_q31.c |
| * Description: Q31 complex magnitude |
| * |
| * $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 groupCmplxMath |
| */ |
| |
| /** |
| @addtogroup cmplx_mag |
| @{ |
| */ |
| |
| /** |
| @brief Q31 complex magnitude. |
| @param[in] pSrc points to input vector |
| @param[out] pDst points to output vector |
| @param[in] numSamples number of samples in each vector |
| @return none |
| |
| @par Scaling and Overflow Behavior |
| The function implements 1.31 by 1.31 multiplications and finally output is converted into 2.30 format. |
| Input down scaling is not required. |
| */ |
| |
| void arm_cmplx_mag_q31( |
| const q31_t * pSrc, |
| q31_t * pDst, |
| uint32_t numSamples) |
| { |
| uint32_t blkCnt; /* Loop counter */ |
| q31_t real, imag; /* Temporary input variables */ |
| q31_t acc0, acc1; /* Accumulators */ |
| |
| #if defined (ARM_MATH_LOOPUNROLL) |
| |
| /* Loop unrolling: Compute 4 outputs at a time */ |
| blkCnt = numSamples >> 2U; |
| |
| while (blkCnt > 0U) |
| { |
| /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */ |
| |
| real = *pSrc++; |
| imag = *pSrc++; |
| acc0 = (q31_t) (((q63_t) real * real) >> 33); |
| acc1 = (q31_t) (((q63_t) imag * imag) >> 33); |
| |
| /* store result in 2.30 format in destination buffer. */ |
| arm_sqrt_q31(acc0 + acc1, pDst++); |
| |
| real = *pSrc++; |
| imag = *pSrc++; |
| acc0 = (q31_t) (((q63_t) real * real) >> 33); |
| acc1 = (q31_t) (((q63_t) imag * imag) >> 33); |
| arm_sqrt_q31(acc0 + acc1, pDst++); |
| |
| real = *pSrc++; |
| imag = *pSrc++; |
| acc0 = (q31_t) (((q63_t) real * real) >> 33); |
| acc1 = (q31_t) (((q63_t) imag * imag) >> 33); |
| arm_sqrt_q31(acc0 + acc1, pDst++); |
| |
| real = *pSrc++; |
| imag = *pSrc++; |
| acc0 = (q31_t) (((q63_t) real * real) >> 33); |
| acc1 = (q31_t) (((q63_t) imag * imag) >> 33); |
| arm_sqrt_q31(acc0 + acc1, pDst++); |
| |
| /* Decrement loop counter */ |
| blkCnt--; |
| } |
| |
| /* Loop unrolling: Compute remaining outputs */ |
| blkCnt = numSamples % 0x4U; |
| |
| #else |
| |
| /* Initialize blkCnt with number of samples */ |
| blkCnt = numSamples; |
| |
| #endif /* #if defined (ARM_MATH_LOOPUNROLL) */ |
| |
| while (blkCnt > 0U) |
| { |
| /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */ |
| |
| real = *pSrc++; |
| imag = *pSrc++; |
| acc0 = (q31_t) (((q63_t) real * real) >> 33); |
| acc1 = (q31_t) (((q63_t) imag * imag) >> 33); |
| |
| /* store result in 2.30 format in destination buffer. */ |
| arm_sqrt_q31(acc0 + acc1, pDst++); |
| |
| /* Decrement loop counter */ |
| blkCnt--; |
| } |
| |
| } |
| |
| /** |
| @} end of cmplx_mag group |
| */ |