mbed-os 6.10 versione
Diff: cmsis_dsp/SupportFunctions/math_helper.c
- Revision:
- 1:fdd22bb7aa52
- Child:
- 2:da51fb522205
diff -r 83d0537c7d84 -r fdd22bb7aa52 cmsis_dsp/SupportFunctions/math_helper.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/SupportFunctions/math_helper.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,447 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 29. November 2010 +* $Revision: V1.0.3 +* +* Project: CMSIS DSP Library +* +* Title: math_helper.c +* +* Description: Definition of all helper functions required. +* +* Target Processor: Cortex-M4/Cortex-M3 +* +* 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. +* +* Version 0.0.7 2010/06/10 +* Misra-C changes done +* -------------------------------------------------------------------- */ + +/* ---------------------------------------------------------------------- +* Include standard header files +* -------------------------------------------------------------------- */ +#include<math.h> + +/* ---------------------------------------------------------------------- +* Include project header files +* -------------------------------------------------------------------- */ +#include "math_helper.h" + +/** + * @brief Caluclation of SNR + * @param float* Pointer to the reference buffer + * @param float* Pointer to the test buffer + * @param uint32_t total number of samples + * @return float SNR + * The function Caluclates signal to noise ratio for the reference output + * and test output + */ + +float arm_snr_f32(float *pRef, float *pTest, uint32_t buffSize) +{ + float EnergySignal = 0.0, EnergyError = 0.0; + uint32_t i; + float SNR; + int temp; + int *test; + + for (i = 0; i < buffSize; i++) + { + /* Checking for a NAN value in pRef array */ + test = (int *)(&pRef[i]); + temp = *test; + + if(temp == 0x7FC00000) + { + return(0); + } + + /* Checking for a NAN value in pTest array */ + test = (int *)(&pTest[i]); + temp = *test; + + if(temp == 0x7FC00000) + { + return(0); + } + EnergySignal += pRef[i] * pRef[i]; + EnergyError += (pRef[i] - pTest[i]) * (pRef[i] - pTest[i]); + } + + /* Checking for a NAN value in EnergyError */ + test = (int *)(&EnergyError); + temp = *test; + + if(temp == 0x7FC00000) + { + return(0); + } + + + SNR = 10 * log10 (EnergySignal / EnergyError); + + return (SNR); + +} + + +/** + * @brief Provide guard bits for Input buffer + * @param q15_t* Pointer to input buffer + * @param uint32_t blockSize + * @param uint32_t guard_bits + * @return none + * The function Provides the guard bits for the buffer + * to avoid overflow + */ + +void arm_provide_guard_bits_q15 (q15_t * input_buf, uint32_t blockSize, + uint32_t guard_bits) +{ + uint32_t i; + + for (i = 0; i < blockSize; i++) + { + input_buf[i] = input_buf[i] >> guard_bits; + } +} + +/** + * @brief Converts float to fixed in q12.20 format + * @param uint32_t number of samples in the buffer + * @return none + * The function converts floating point values to fixed point(q12.20) values + */ + +void arm_float_to_q12_20(float *pIn, q31_t * pOut, uint32_t numSamples) +{ + uint32_t i; + + for (i = 0; i < numSamples; i++) + { + /* 1048576.0f corresponds to pow(2, 20) */ + pOut[i] = (q31_t) (pIn[i] * 1048576.0f); + + pOut[i] += pIn[i] > 0 ? 0.5 : -0.5; + + if (pIn[i] == (float) 1.0) + { + pOut[i] = 0x000FFFFF; + } + } +} + +/** + * @brief Compare MATLAB Reference Output and ARM Test output + * @param q15_t* Pointer to Ref buffer + * @param q15_t* Pointer to Test buffer + * @param uint32_t number of samples in the buffer + * @return none + */ + +uint32_t arm_compare_fixed_q15(q15_t *pIn, q15_t * pOut, uint32_t numSamples) +{ + uint32_t i; + int32_t diff, diffCrnt = 0; + uint32_t maxDiff = 0; + + for (i = 0; i < numSamples; i++) + { + diff = pIn[i] - pOut[i]; + diffCrnt = (diff > 0) ? diff : -diff; + + if(diffCrnt > maxDiff) + { + maxDiff = diffCrnt; + } + } + + return(maxDiff); +} + +/** + * @brief Compare MATLAB Reference Output and ARM Test output + * @param q31_t* Pointer to Ref buffer + * @param q31_t* Pointer to Test buffer + * @param uint32_t number of samples in the buffer + * @return none + */ + +uint32_t arm_compare_fixed_q31(q31_t *pIn, q31_t * pOut, uint32_t numSamples) +{ + uint32_t i; + int32_t diff, diffCrnt = 0; + uint32_t maxDiff = 0; + + for (i = 0; i < numSamples; i++) + { + diff = pIn[i] - pOut[i]; + diffCrnt = (diff > 0) ? diff : -diff; + + if(diffCrnt > maxDiff) + { + maxDiff = diffCrnt; + } + } + + return(maxDiff); +} + +/** + * @brief Provide guard bits for Input buffer + * @param q31_t* Pointer to input buffer + * @param uint32_t blockSize + * @param uint32_t guard_bits + * @return none + * The function Provides the guard bits for the buffer + * to avoid overflow + */ + +void arm_provide_guard_bits_q31 (q31_t * input_buf, + uint32_t blockSize, + uint32_t guard_bits) +{ + uint32_t i; + + for (i = 0; i < blockSize; i++) + { + input_buf[i] = input_buf[i] >> guard_bits; + } +} + +/** + * @brief Provide guard bits for Input buffer + * @param q31_t* Pointer to input buffer + * @param uint32_t blockSize + * @param uint32_t guard_bits + * @return none + * The function Provides the guard bits for the buffer + * to avoid overflow + */ + +void arm_provide_guard_bits_q7 (q7_t * input_buf, + uint32_t blockSize, + uint32_t guard_bits) +{ + uint32_t i; + + for (i = 0; i < blockSize; i++) + { + input_buf[i] = input_buf[i] >> guard_bits; + } +} + + + +/** + * @brief Caluclates number of guard bits + * @param uint32_t number of additions + * @return none + * The function Caluclates the number of guard bits + * depending on the numtaps + */ + +uint32_t arm_calc_guard_bits (uint32_t num_adds) +{ + uint32_t i = 1, j = 0; + + if (num_adds == 1) + { + return (0); + } + + while (i < num_adds) + { + i = i * 2; + j++; + } + + return (j); +} + +/** + * @brief Converts Q15 to floating-point + * @param uint32_t number of samples in the buffer + * @return none + */ + +void arm_apply_guard_bits (float32_t * pIn, + uint32_t numSamples, + uint32_t guard_bits) +{ + uint32_t i; + + for (i = 0; i < numSamples; i++) + { + pIn[i] = pIn[i] * arm_calc_2pow(guard_bits); + } +} + +/** + * @brief Calculates pow(2, numShifts) + * @param uint32_t number of shifts + * @return pow(2, numShifts) + */ +uint32_t arm_calc_2pow(uint32_t numShifts) +{ + + uint32_t i, val = 1; + + for (i = 0; i < numShifts; i++) + { + val = val * 2; + } + + return(val); +} + + + +/** + * @brief Converts float to fixed q14 + * @param uint32_t number of samples in the buffer + * @return none + * The function converts floating point values to fixed point values + */ + +void arm_float_to_q14 (float *pIn, q15_t * pOut, + uint32_t numSamples) +{ + uint32_t i; + + for (i = 0; i < numSamples; i++) + { + /* 16384.0f corresponds to pow(2, 14) */ + pOut[i] = (q15_t) (pIn[i] * 16384.0f); + + pOut[i] += pIn[i] > 0 ? 0.5 : -0.5; + + if (pIn[i] == (float) 2.0) + { + pOut[i] = 0x7FFF; + } + + } + +} + + +/** + * @brief Converts float to fixed q30 format + * @param uint32_t number of samples in the buffer + * @return none + * The function converts floating point values to fixed point values + */ + +void arm_float_to_q30 (float *pIn, q31_t * pOut, + uint32_t numSamples) +{ + uint32_t i; + + for (i = 0; i < numSamples; i++) + { + /* 1073741824.0f corresponds to pow(2, 30) */ + pOut[i] = (q31_t) (pIn[i] * 1073741824.0f); + + pOut[i] += pIn[i] > 0 ? 0.5 : -0.5; + + if (pIn[i] == (float) 2.0) + { + pOut[i] = 0x7FFFFFFF; + } + } +} + +/** + * @brief Converts float to fixed q30 format + * @param uint32_t number of samples in the buffer + * @return none + * The function converts floating point values to fixed point values + */ + +void arm_float_to_q29 (float *pIn, q31_t * pOut, + uint32_t numSamples) +{ + uint32_t i; + + for (i = 0; i < numSamples; i++) + { + /* 1073741824.0f corresponds to pow(2, 30) */ + pOut[i] = (q31_t) (pIn[i] * 536870912.0f); + + pOut[i] += pIn[i] > 0 ? 0.5 : -0.5; + + if (pIn[i] == (float) 4.0) + { + pOut[i] = 0x7FFFFFFF; + } + } +} + + +/** + * @brief Converts float to fixed q28 format + * @param uint32_t number of samples in the buffer + * @return none + * The function converts floating point values to fixed point values + */ + +void arm_float_to_q28 (float *pIn, q31_t * pOut, + uint32_t numSamples) +{ + uint32_t i; + + for (i = 0; i < numSamples; i++) + { + /* 268435456.0f corresponds to pow(2, 28) */ + pOut[i] = (q31_t) (pIn[i] * 268435456.0f); + + pOut[i] += pIn[i] > 0 ? 0.5 : -0.5; + + if (pIn[i] == (float) 8.0) + { + pOut[i] = 0x7FFFFFFF; + } + } +} + +/** + * @brief Clip the float values to +/- 1 + * @param pIn input buffer + * @param numSamples number of samples in the buffer + * @return none + * The function converts floating point values to fixed point values + */ + +void arm_clip_f32 (float *pIn, uint32_t numSamples) +{ + uint32_t i; + + for (i = 0; i < numSamples; i++) + { + if(pIn[i] > 1.0f) + { + pIn[i] = 1.0; + } + else if( pIn[i] < -1.0f) + { + pIn[i] = -1.0; + } + + } +} + + + +