mbed-os 6.10 versione
Diff: cmsis_dsp/ComplexMathFunctions/arm_cmplx_mag_q31.c
- Revision:
- 1:fdd22bb7aa52
- Child:
- 2:da51fb522205
diff -r 83d0537c7d84 -r fdd22bb7aa52 cmsis_dsp/ComplexMathFunctions/arm_cmplx_mag_q31.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/ComplexMathFunctions/arm_cmplx_mag_q31.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,177 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_cmplx_mag_q31.c +* +* Description: Q31 complex magnitude +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Version 1.1.0 2012/02/15 +* Updated with more optimizations, bug fixes and minor API changes. +* +* Version 1.0.10 2011/7/15 +* Big Endian support added and Merged M0 and M3/M4 Source code. +* +* Version 1.0.3 2010/11/29 +* Re-organized the CMSIS folders and updated documentation. +* +* Version 1.0.2 2010/11/11 +* Documentation updated. +* +* Version 1.0.1 2010/10/05 +* Production release and review comments incorporated. +* +* Version 1.0.0 2010/09/20 +* Production release and review comments incorporated. +* ---------------------------------------------------------------------------- */ + +#include "arm_math.h" + +/** + * @ingroup groupCmplxMath + */ + +/** + * @addtogroup cmplx_mag + * @{ + */ + +/** + * @brief Q31 complex magnitude + * @param *pSrc points to the complex input vector + * @param *pDst points to the real output vector + * @param numSamples number of complex samples in the input vector + * @return none. + * + * <b>Scaling and Overflow Behavior:</b> + * \par + * 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( + q31_t * pSrc, + q31_t * pDst, + uint32_t numSamples) +{ + q31_t real, imag; /* Temporary variables to hold input values */ + q31_t acc0, acc1; /* Accumulators */ + uint32_t blkCnt; /* loop counter */ + +#ifndef ARM_MATH_CM0 + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + q31_t real1, real2, imag1, imag2; /* Temporary variables to hold input values */ + q31_t out1, out2, out3, out4; /* Accumulators */ + q63_t mul1, mul2, mul3, mul4; /* Temporary variables */ + + + /*loop Unrolling */ + blkCnt = numSamples >> 2u; + + /* First part of the processing with loop unrolling. Compute 4 outputs at a time. + ** a second loop below computes the remaining 1 to 3 samples. */ + while(blkCnt > 0u) + { + /* read complex input from source buffer */ + real1 = pSrc[0]; + imag1 = pSrc[1]; + real2 = pSrc[2]; + imag2 = pSrc[3]; + + /* calculate power of input values */ + mul1 = (q63_t) real1 *real1; + mul2 = (q63_t) imag1 *imag1; + mul3 = (q63_t) real2 *real2; + mul4 = (q63_t) imag2 *imag2; + + /* get the result to 3.29 format */ + out1 = (q31_t) (mul1 >> 33); + out2 = (q31_t) (mul2 >> 33); + out3 = (q31_t) (mul3 >> 33); + out4 = (q31_t) (mul4 >> 33); + + /* add real and imaginary accumulators */ + out1 = out1 + out2; + out3 = out3 + out4; + + /* read complex input from source buffer */ + real1 = pSrc[4]; + imag1 = pSrc[5]; + real2 = pSrc[6]; + imag2 = pSrc[7]; + + /* calculate square root */ + arm_sqrt_q31(out1, &pDst[0]); + + /* calculate power of input values */ + mul1 = (q63_t) real1 *real1; + + /* calculate square root */ + arm_sqrt_q31(out3, &pDst[1]); + + /* calculate power of input values */ + mul2 = (q63_t) imag1 *imag1; + mul3 = (q63_t) real2 *real2; + mul4 = (q63_t) imag2 *imag2; + + /* get the result to 3.29 format */ + out1 = (q31_t) (mul1 >> 33); + out2 = (q31_t) (mul2 >> 33); + out3 = (q31_t) (mul3 >> 33); + out4 = (q31_t) (mul4 >> 33); + + /* add real and imaginary accumulators */ + out1 = out1 + out2; + out3 = out3 + out4; + + /* calculate square root */ + arm_sqrt_q31(out1, &pDst[2]); + + /* increment destination by 8 to process next samples */ + pSrc += 8u; + + /* calculate square root */ + arm_sqrt_q31(out3, &pDst[3]); + + /* increment destination by 4 to process next samples */ + pDst += 4u; + + /* Decrement the loop counter */ + blkCnt--; + } + + /* If the numSamples is not a multiple of 4, compute any remaining output samples here. + ** No loop unrolling is used. */ + blkCnt = numSamples % 0x4u; + +#else + + /* Run the below code for Cortex-M0 */ + blkCnt = numSamples; + +#endif /* #ifndef ARM_MATH_CM0 */ + + 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 the result in 2.30 format in the destination buffer. */ + arm_sqrt_q31(acc0 + acc1, pDst++); + + /* Decrement the loop counter */ + blkCnt--; + } +} + +/** + * @} end of cmplx_mag group + */