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CMSIS DSP library

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cmsis_dsp/SupportFunctions/math_helper.c@1:fdd22bb7aa52, 2012-11-28 (annotated)

Committer:
emilmont
Date:
Wed Nov 28 12:30:09 2012 +0000
Revision:
1:fdd22bb7aa52
Child:
2:da51fb522205
DSP library code

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 1:fdd22bb7aa52 1 /* ----------------------------------------------------------------------
emilmont 1:fdd22bb7aa52 2 * Copyright (C) 2010 ARM Limited. All rights reserved.
emilmont 1:fdd22bb7aa52 3 *
emilmont 1:fdd22bb7aa52 4 * $Date: 29. November 2010
emilmont 1:fdd22bb7aa52 5 * $Revision: V1.0.3
emilmont 1:fdd22bb7aa52 6 *
emilmont 1:fdd22bb7aa52 7 * Project: CMSIS DSP Library
emilmont 1:fdd22bb7aa52 8 *
emilmont 1:fdd22bb7aa52 9 * Title: math_helper.c
emilmont 1:fdd22bb7aa52 10 *
emilmont 1:fdd22bb7aa52 11 * Description: Definition of all helper functions required.
emilmont 1:fdd22bb7aa52 12 *
emilmont 1:fdd22bb7aa52 13 * Target Processor: Cortex-M4/Cortex-M3
emilmont 1:fdd22bb7aa52 14 *
emilmont 1:fdd22bb7aa52 15 * Version 1.0.3 2010/11/29
emilmont 1:fdd22bb7aa52 16 * Re-organized the CMSIS folders and updated documentation.
emilmont 1:fdd22bb7aa52 17 *
emilmont 1:fdd22bb7aa52 18 * Version 1.0.2 2010/11/11
emilmont 1:fdd22bb7aa52 19 * Documentation updated.
emilmont 1:fdd22bb7aa52 20 *
emilmont 1:fdd22bb7aa52 21 * Version 1.0.1 2010/10/05
emilmont 1:fdd22bb7aa52 22 * Production release and review comments incorporated.
emilmont 1:fdd22bb7aa52 23 *
emilmont 1:fdd22bb7aa52 24 * Version 1.0.0 2010/09/20
emilmont 1:fdd22bb7aa52 25 * Production release and review comments incorporated.
emilmont 1:fdd22bb7aa52 26 *
emilmont 1:fdd22bb7aa52 27 * Version 0.0.7 2010/06/10
emilmont 1:fdd22bb7aa52 28 * Misra-C changes done
emilmont 1:fdd22bb7aa52 29 * -------------------------------------------------------------------- */
emilmont 1:fdd22bb7aa52 30
emilmont 1:fdd22bb7aa52 31 /* ----------------------------------------------------------------------
emilmont 1:fdd22bb7aa52 32 * Include standard header files
emilmont 1:fdd22bb7aa52 33 * -------------------------------------------------------------------- */
emilmont 1:fdd22bb7aa52 34 #include<math.h>
emilmont 1:fdd22bb7aa52 35
emilmont 1:fdd22bb7aa52 36 /* ----------------------------------------------------------------------
emilmont 1:fdd22bb7aa52 37 * Include project header files
emilmont 1:fdd22bb7aa52 38 * -------------------------------------------------------------------- */
emilmont 1:fdd22bb7aa52 39 #include "math_helper.h"
emilmont 1:fdd22bb7aa52 40
emilmont 1:fdd22bb7aa52 41 /**
emilmont 1:fdd22bb7aa52 42 * @brief Caluclation of SNR
emilmont 1:fdd22bb7aa52 43 * @param float* Pointer to the reference buffer
emilmont 1:fdd22bb7aa52 44 * @param float* Pointer to the test buffer
emilmont 1:fdd22bb7aa52 45 * @param uint32_t total number of samples
emilmont 1:fdd22bb7aa52 46 * @return float SNR
emilmont 1:fdd22bb7aa52 47 * The function Caluclates signal to noise ratio for the reference output
emilmont 1:fdd22bb7aa52 48 * and test output
emilmont 1:fdd22bb7aa52 49 */
emilmont 1:fdd22bb7aa52 50
emilmont 1:fdd22bb7aa52 51 float arm_snr_f32(float *pRef, float *pTest, uint32_t buffSize)
emilmont 1:fdd22bb7aa52 52 {
emilmont 1:fdd22bb7aa52 53 float EnergySignal = 0.0, EnergyError = 0.0;
emilmont 1:fdd22bb7aa52 54 uint32_t i;
emilmont 1:fdd22bb7aa52 55 float SNR;
emilmont 1:fdd22bb7aa52 56 int temp;
emilmont 1:fdd22bb7aa52 57 int *test;
emilmont 1:fdd22bb7aa52 58
emilmont 1:fdd22bb7aa52 59 for (i = 0; i < buffSize; i++)
emilmont 1:fdd22bb7aa52 60 {
emilmont 1:fdd22bb7aa52 61 /* Checking for a NAN value in pRef array */
emilmont 1:fdd22bb7aa52 62 test = (int *)(&pRef[i]);
emilmont 1:fdd22bb7aa52 63 temp = *test;
emilmont 1:fdd22bb7aa52 64
emilmont 1:fdd22bb7aa52 65 if(temp == 0x7FC00000)
emilmont 1:fdd22bb7aa52 66 {
emilmont 1:fdd22bb7aa52 67 return(0);
emilmont 1:fdd22bb7aa52 68 }
emilmont 1:fdd22bb7aa52 69
emilmont 1:fdd22bb7aa52 70 /* Checking for a NAN value in pTest array */
emilmont 1:fdd22bb7aa52 71 test = (int *)(&pTest[i]);
emilmont 1:fdd22bb7aa52 72 temp = *test;
emilmont 1:fdd22bb7aa52 73
emilmont 1:fdd22bb7aa52 74 if(temp == 0x7FC00000)
emilmont 1:fdd22bb7aa52 75 {
emilmont 1:fdd22bb7aa52 76 return(0);
emilmont 1:fdd22bb7aa52 77 }
emilmont 1:fdd22bb7aa52 78 EnergySignal += pRef[i] * pRef[i];
emilmont 1:fdd22bb7aa52 79 EnergyError += (pRef[i] - pTest[i]) * (pRef[i] - pTest[i]);
emilmont 1:fdd22bb7aa52 80 }
emilmont 1:fdd22bb7aa52 81
emilmont 1:fdd22bb7aa52 82 /* Checking for a NAN value in EnergyError */
emilmont 1:fdd22bb7aa52 83 test = (int *)(&EnergyError);
emilmont 1:fdd22bb7aa52 84 temp = *test;
emilmont 1:fdd22bb7aa52 85
emilmont 1:fdd22bb7aa52 86 if(temp == 0x7FC00000)
emilmont 1:fdd22bb7aa52 87 {
emilmont 1:fdd22bb7aa52 88 return(0);
emilmont 1:fdd22bb7aa52 89 }
emilmont 1:fdd22bb7aa52 90
emilmont 1:fdd22bb7aa52 91
emilmont 1:fdd22bb7aa52 92 SNR = 10 * log10 (EnergySignal / EnergyError);
emilmont 1:fdd22bb7aa52 93
emilmont 1:fdd22bb7aa52 94 return (SNR);
emilmont 1:fdd22bb7aa52 95
emilmont 1:fdd22bb7aa52 96 }
emilmont 1:fdd22bb7aa52 97
emilmont 1:fdd22bb7aa52 98
emilmont 1:fdd22bb7aa52 99 /**
emilmont 1:fdd22bb7aa52 100 * @brief Provide guard bits for Input buffer
emilmont 1:fdd22bb7aa52 101 * @param q15_t* Pointer to input buffer
emilmont 1:fdd22bb7aa52 102 * @param uint32_t blockSize
emilmont 1:fdd22bb7aa52 103 * @param uint32_t guard_bits
emilmont 1:fdd22bb7aa52 104 * @return none
emilmont 1:fdd22bb7aa52 105 * The function Provides the guard bits for the buffer
emilmont 1:fdd22bb7aa52 106 * to avoid overflow
emilmont 1:fdd22bb7aa52 107 */
emilmont 1:fdd22bb7aa52 108
emilmont 1:fdd22bb7aa52 109 void arm_provide_guard_bits_q15 (q15_t * input_buf, uint32_t blockSize,
emilmont 1:fdd22bb7aa52 110 uint32_t guard_bits)
emilmont 1:fdd22bb7aa52 111 {
emilmont 1:fdd22bb7aa52 112 uint32_t i;
emilmont 1:fdd22bb7aa52 113
emilmont 1:fdd22bb7aa52 114 for (i = 0; i < blockSize; i++)
emilmont 1:fdd22bb7aa52 115 {
emilmont 1:fdd22bb7aa52 116 input_buf[i] = input_buf[i] >> guard_bits;
emilmont 1:fdd22bb7aa52 117 }
emilmont 1:fdd22bb7aa52 118 }
emilmont 1:fdd22bb7aa52 119
emilmont 1:fdd22bb7aa52 120 /**
emilmont 1:fdd22bb7aa52 121 * @brief Converts float to fixed in q12.20 format
emilmont 1:fdd22bb7aa52 122 * @param uint32_t number of samples in the buffer
emilmont 1:fdd22bb7aa52 123 * @return none
emilmont 1:fdd22bb7aa52 124 * The function converts floating point values to fixed point(q12.20) values
emilmont 1:fdd22bb7aa52 125 */
emilmont 1:fdd22bb7aa52 126
emilmont 1:fdd22bb7aa52 127 void arm_float_to_q12_20(float *pIn, q31_t * pOut, uint32_t numSamples)
emilmont 1:fdd22bb7aa52 128 {
emilmont 1:fdd22bb7aa52 129 uint32_t i;
emilmont 1:fdd22bb7aa52 130
emilmont 1:fdd22bb7aa52 131 for (i = 0; i < numSamples; i++)
emilmont 1:fdd22bb7aa52 132 {
emilmont 1:fdd22bb7aa52 133 /* 1048576.0f corresponds to pow(2, 20) */
emilmont 1:fdd22bb7aa52 134 pOut[i] = (q31_t) (pIn[i] * 1048576.0f);
emilmont 1:fdd22bb7aa52 135
emilmont 1:fdd22bb7aa52 136 pOut[i] += pIn[i] > 0 ? 0.5 : -0.5;
emilmont 1:fdd22bb7aa52 137
emilmont 1:fdd22bb7aa52 138 if (pIn[i] == (float) 1.0)
emilmont 1:fdd22bb7aa52 139 {
emilmont 1:fdd22bb7aa52 140 pOut[i] = 0x000FFFFF;
emilmont 1:fdd22bb7aa52 141 }
emilmont 1:fdd22bb7aa52 142 }
emilmont 1:fdd22bb7aa52 143 }
emilmont 1:fdd22bb7aa52 144
emilmont 1:fdd22bb7aa52 145 /**
emilmont 1:fdd22bb7aa52 146 * @brief Compare MATLAB Reference Output and ARM Test output
emilmont 1:fdd22bb7aa52 147 * @param q15_t* Pointer to Ref buffer
emilmont 1:fdd22bb7aa52 148 * @param q15_t* Pointer to Test buffer
emilmont 1:fdd22bb7aa52 149 * @param uint32_t number of samples in the buffer
emilmont 1:fdd22bb7aa52 150 * @return none
emilmont 1:fdd22bb7aa52 151 */
emilmont 1:fdd22bb7aa52 152
emilmont 1:fdd22bb7aa52 153 uint32_t arm_compare_fixed_q15(q15_t *pIn, q15_t * pOut, uint32_t numSamples)
emilmont 1:fdd22bb7aa52 154 {
emilmont 1:fdd22bb7aa52 155 uint32_t i;
emilmont 1:fdd22bb7aa52 156 int32_t diff, diffCrnt = 0;
emilmont 1:fdd22bb7aa52 157 uint32_t maxDiff = 0;
emilmont 1:fdd22bb7aa52 158
emilmont 1:fdd22bb7aa52 159 for (i = 0; i < numSamples; i++)
emilmont 1:fdd22bb7aa52 160 {
emilmont 1:fdd22bb7aa52 161 diff = pIn[i] - pOut[i];
emilmont 1:fdd22bb7aa52 162 diffCrnt = (diff > 0) ? diff : -diff;
emilmont 1:fdd22bb7aa52 163
emilmont 1:fdd22bb7aa52 164 if(diffCrnt > maxDiff)
emilmont 1:fdd22bb7aa52 165 {
emilmont 1:fdd22bb7aa52 166 maxDiff = diffCrnt;
emilmont 1:fdd22bb7aa52 167 }
emilmont 1:fdd22bb7aa52 168 }
emilmont 1:fdd22bb7aa52 169
emilmont 1:fdd22bb7aa52 170 return(maxDiff);
emilmont 1:fdd22bb7aa52 171 }
emilmont 1:fdd22bb7aa52 172
emilmont 1:fdd22bb7aa52 173 /**
emilmont 1:fdd22bb7aa52 174 * @brief Compare MATLAB Reference Output and ARM Test output
emilmont 1:fdd22bb7aa52 175 * @param q31_t* Pointer to Ref buffer
emilmont 1:fdd22bb7aa52 176 * @param q31_t* Pointer to Test buffer
emilmont 1:fdd22bb7aa52 177 * @param uint32_t number of samples in the buffer
emilmont 1:fdd22bb7aa52 178 * @return none
emilmont 1:fdd22bb7aa52 179 */
emilmont 1:fdd22bb7aa52 180
emilmont 1:fdd22bb7aa52 181 uint32_t arm_compare_fixed_q31(q31_t *pIn, q31_t * pOut, uint32_t numSamples)
emilmont 1:fdd22bb7aa52 182 {
emilmont 1:fdd22bb7aa52 183 uint32_t i;
emilmont 1:fdd22bb7aa52 184 int32_t diff, diffCrnt = 0;
emilmont 1:fdd22bb7aa52 185 uint32_t maxDiff = 0;
emilmont 1:fdd22bb7aa52 186
emilmont 1:fdd22bb7aa52 187 for (i = 0; i < numSamples; i++)
emilmont 1:fdd22bb7aa52 188 {
emilmont 1:fdd22bb7aa52 189 diff = pIn[i] - pOut[i];
emilmont 1:fdd22bb7aa52 190 diffCrnt = (diff > 0) ? diff : -diff;
emilmont 1:fdd22bb7aa52 191
emilmont 1:fdd22bb7aa52 192 if(diffCrnt > maxDiff)
emilmont 1:fdd22bb7aa52 193 {
emilmont 1:fdd22bb7aa52 194 maxDiff = diffCrnt;
emilmont 1:fdd22bb7aa52 195 }
emilmont 1:fdd22bb7aa52 196 }
emilmont 1:fdd22bb7aa52 197
emilmont 1:fdd22bb7aa52 198 return(maxDiff);
emilmont 1:fdd22bb7aa52 199 }
emilmont 1:fdd22bb7aa52 200
emilmont 1:fdd22bb7aa52 201 /**
emilmont 1:fdd22bb7aa52 202 * @brief Provide guard bits for Input buffer
emilmont 1:fdd22bb7aa52 203 * @param q31_t* Pointer to input buffer
emilmont 1:fdd22bb7aa52 204 * @param uint32_t blockSize
emilmont 1:fdd22bb7aa52 205 * @param uint32_t guard_bits
emilmont 1:fdd22bb7aa52 206 * @return none
emilmont 1:fdd22bb7aa52 207 * The function Provides the guard bits for the buffer
emilmont 1:fdd22bb7aa52 208 * to avoid overflow
emilmont 1:fdd22bb7aa52 209 */
emilmont 1:fdd22bb7aa52 210
emilmont 1:fdd22bb7aa52 211 void arm_provide_guard_bits_q31 (q31_t * input_buf,
emilmont 1:fdd22bb7aa52 212 uint32_t blockSize,
emilmont 1:fdd22bb7aa52 213 uint32_t guard_bits)
emilmont 1:fdd22bb7aa52 214 {
emilmont 1:fdd22bb7aa52 215 uint32_t i;
emilmont 1:fdd22bb7aa52 216
emilmont 1:fdd22bb7aa52 217 for (i = 0; i < blockSize; i++)
emilmont 1:fdd22bb7aa52 218 {
emilmont 1:fdd22bb7aa52 219 input_buf[i] = input_buf[i] >> guard_bits;
emilmont 1:fdd22bb7aa52 220 }
emilmont 1:fdd22bb7aa52 221 }
emilmont 1:fdd22bb7aa52 222
emilmont 1:fdd22bb7aa52 223 /**
emilmont 1:fdd22bb7aa52 224 * @brief Provide guard bits for Input buffer
emilmont 1:fdd22bb7aa52 225 * @param q31_t* Pointer to input buffer
emilmont 1:fdd22bb7aa52 226 * @param uint32_t blockSize
emilmont 1:fdd22bb7aa52 227 * @param uint32_t guard_bits
emilmont 1:fdd22bb7aa52 228 * @return none
emilmont 1:fdd22bb7aa52 229 * The function Provides the guard bits for the buffer
emilmont 1:fdd22bb7aa52 230 * to avoid overflow
emilmont 1:fdd22bb7aa52 231 */
emilmont 1:fdd22bb7aa52 232
emilmont 1:fdd22bb7aa52 233 void arm_provide_guard_bits_q7 (q7_t * input_buf,
emilmont 1:fdd22bb7aa52 234 uint32_t blockSize,
emilmont 1:fdd22bb7aa52 235 uint32_t guard_bits)
emilmont 1:fdd22bb7aa52 236 {
emilmont 1:fdd22bb7aa52 237 uint32_t i;
emilmont 1:fdd22bb7aa52 238
emilmont 1:fdd22bb7aa52 239 for (i = 0; i < blockSize; i++)
emilmont 1:fdd22bb7aa52 240 {
emilmont 1:fdd22bb7aa52 241 input_buf[i] = input_buf[i] >> guard_bits;
emilmont 1:fdd22bb7aa52 242 }
emilmont 1:fdd22bb7aa52 243 }
emilmont 1:fdd22bb7aa52 244
emilmont 1:fdd22bb7aa52 245
emilmont 1:fdd22bb7aa52 246
emilmont 1:fdd22bb7aa52 247 /**
emilmont 1:fdd22bb7aa52 248 * @brief Caluclates number of guard bits
emilmont 1:fdd22bb7aa52 249 * @param uint32_t number of additions
emilmont 1:fdd22bb7aa52 250 * @return none
emilmont 1:fdd22bb7aa52 251 * The function Caluclates the number of guard bits
emilmont 1:fdd22bb7aa52 252 * depending on the numtaps
emilmont 1:fdd22bb7aa52 253 */
emilmont 1:fdd22bb7aa52 254
emilmont 1:fdd22bb7aa52 255 uint32_t arm_calc_guard_bits (uint32_t num_adds)
emilmont 1:fdd22bb7aa52 256 {
emilmont 1:fdd22bb7aa52 257 uint32_t i = 1, j = 0;
emilmont 1:fdd22bb7aa52 258
emilmont 1:fdd22bb7aa52 259 if (num_adds == 1)
emilmont 1:fdd22bb7aa52 260 {
emilmont 1:fdd22bb7aa52 261 return (0);
emilmont 1:fdd22bb7aa52 262 }
emilmont 1:fdd22bb7aa52 263
emilmont 1:fdd22bb7aa52 264 while (i < num_adds)
emilmont 1:fdd22bb7aa52 265 {
emilmont 1:fdd22bb7aa52 266 i = i * 2;
emilmont 1:fdd22bb7aa52 267 j++;
emilmont 1:fdd22bb7aa52 268 }
emilmont 1:fdd22bb7aa52 269
emilmont 1:fdd22bb7aa52 270 return (j);
emilmont 1:fdd22bb7aa52 271 }
emilmont 1:fdd22bb7aa52 272
emilmont 1:fdd22bb7aa52 273 /**
emilmont 1:fdd22bb7aa52 274 * @brief Converts Q15 to floating-point
emilmont 1:fdd22bb7aa52 275 * @param uint32_t number of samples in the buffer
emilmont 1:fdd22bb7aa52 276 * @return none
emilmont 1:fdd22bb7aa52 277 */
emilmont 1:fdd22bb7aa52 278
emilmont 1:fdd22bb7aa52 279 void arm_apply_guard_bits (float32_t * pIn,
emilmont 1:fdd22bb7aa52 280 uint32_t numSamples,
emilmont 1:fdd22bb7aa52 281 uint32_t guard_bits)
emilmont 1:fdd22bb7aa52 282 {
emilmont 1:fdd22bb7aa52 283 uint32_t i;
emilmont 1:fdd22bb7aa52 284
emilmont 1:fdd22bb7aa52 285 for (i = 0; i < numSamples; i++)
emilmont 1:fdd22bb7aa52 286 {
emilmont 1:fdd22bb7aa52 287 pIn[i] = pIn[i] * arm_calc_2pow(guard_bits);
emilmont 1:fdd22bb7aa52 288 }
emilmont 1:fdd22bb7aa52 289 }
emilmont 1:fdd22bb7aa52 290
emilmont 1:fdd22bb7aa52 291 /**
emilmont 1:fdd22bb7aa52 292 * @brief Calculates pow(2, numShifts)
emilmont 1:fdd22bb7aa52 293 * @param uint32_t number of shifts
emilmont 1:fdd22bb7aa52 294 * @return pow(2, numShifts)
emilmont 1:fdd22bb7aa52 295 */
emilmont 1:fdd22bb7aa52 296 uint32_t arm_calc_2pow(uint32_t numShifts)
emilmont 1:fdd22bb7aa52 297 {
emilmont 1:fdd22bb7aa52 298
emilmont 1:fdd22bb7aa52 299 uint32_t i, val = 1;
emilmont 1:fdd22bb7aa52 300
emilmont 1:fdd22bb7aa52 301 for (i = 0; i < numShifts; i++)
emilmont 1:fdd22bb7aa52 302 {
emilmont 1:fdd22bb7aa52 303 val = val * 2;
emilmont 1:fdd22bb7aa52 304 }
emilmont 1:fdd22bb7aa52 305
emilmont 1:fdd22bb7aa52 306 return(val);
emilmont 1:fdd22bb7aa52 307 }
emilmont 1:fdd22bb7aa52 308
emilmont 1:fdd22bb7aa52 309
emilmont 1:fdd22bb7aa52 310
emilmont 1:fdd22bb7aa52 311 /**
emilmont 1:fdd22bb7aa52 312 * @brief Converts float to fixed q14
emilmont 1:fdd22bb7aa52 313 * @param uint32_t number of samples in the buffer
emilmont 1:fdd22bb7aa52 314 * @return none
emilmont 1:fdd22bb7aa52 315 * The function converts floating point values to fixed point values
emilmont 1:fdd22bb7aa52 316 */
emilmont 1:fdd22bb7aa52 317
emilmont 1:fdd22bb7aa52 318 void arm_float_to_q14 (float *pIn, q15_t * pOut,
emilmont 1:fdd22bb7aa52 319 uint32_t numSamples)
emilmont 1:fdd22bb7aa52 320 {
emilmont 1:fdd22bb7aa52 321 uint32_t i;
emilmont 1:fdd22bb7aa52 322
emilmont 1:fdd22bb7aa52 323 for (i = 0; i < numSamples; i++)
emilmont 1:fdd22bb7aa52 324 {
emilmont 1:fdd22bb7aa52 325 /* 16384.0f corresponds to pow(2, 14) */
emilmont 1:fdd22bb7aa52 326 pOut[i] = (q15_t) (pIn[i] * 16384.0f);
emilmont 1:fdd22bb7aa52 327
emilmont 1:fdd22bb7aa52 328 pOut[i] += pIn[i] > 0 ? 0.5 : -0.5;
emilmont 1:fdd22bb7aa52 329
emilmont 1:fdd22bb7aa52 330 if (pIn[i] == (float) 2.0)
emilmont 1:fdd22bb7aa52 331 {
emilmont 1:fdd22bb7aa52 332 pOut[i] = 0x7FFF;
emilmont 1:fdd22bb7aa52 333 }
emilmont 1:fdd22bb7aa52 334
emilmont 1:fdd22bb7aa52 335 }
emilmont 1:fdd22bb7aa52 336
emilmont 1:fdd22bb7aa52 337 }
emilmont 1:fdd22bb7aa52 338
emilmont 1:fdd22bb7aa52 339
emilmont 1:fdd22bb7aa52 340 /**
emilmont 1:fdd22bb7aa52 341 * @brief Converts float to fixed q30 format
emilmont 1:fdd22bb7aa52 342 * @param uint32_t number of samples in the buffer
emilmont 1:fdd22bb7aa52 343 * @return none
emilmont 1:fdd22bb7aa52 344 * The function converts floating point values to fixed point values
emilmont 1:fdd22bb7aa52 345 */
emilmont 1:fdd22bb7aa52 346
emilmont 1:fdd22bb7aa52 347 void arm_float_to_q30 (float *pIn, q31_t * pOut,
emilmont 1:fdd22bb7aa52 348 uint32_t numSamples)
emilmont 1:fdd22bb7aa52 349 {
emilmont 1:fdd22bb7aa52 350 uint32_t i;
emilmont 1:fdd22bb7aa52 351
emilmont 1:fdd22bb7aa52 352 for (i = 0; i < numSamples; i++)
emilmont 1:fdd22bb7aa52 353 {
emilmont 1:fdd22bb7aa52 354 /* 1073741824.0f corresponds to pow(2, 30) */
emilmont 1:fdd22bb7aa52 355 pOut[i] = (q31_t) (pIn[i] * 1073741824.0f);
emilmont 1:fdd22bb7aa52 356
emilmont 1:fdd22bb7aa52 357 pOut[i] += pIn[i] > 0 ? 0.5 : -0.5;
emilmont 1:fdd22bb7aa52 358
emilmont 1:fdd22bb7aa52 359 if (pIn[i] == (float) 2.0)
emilmont 1:fdd22bb7aa52 360 {
emilmont 1:fdd22bb7aa52 361 pOut[i] = 0x7FFFFFFF;
emilmont 1:fdd22bb7aa52 362 }
emilmont 1:fdd22bb7aa52 363 }
emilmont 1:fdd22bb7aa52 364 }
emilmont 1:fdd22bb7aa52 365
emilmont 1:fdd22bb7aa52 366 /**
emilmont 1:fdd22bb7aa52 367 * @brief Converts float to fixed q30 format
emilmont 1:fdd22bb7aa52 368 * @param uint32_t number of samples in the buffer
emilmont 1:fdd22bb7aa52 369 * @return none
emilmont 1:fdd22bb7aa52 370 * The function converts floating point values to fixed point values
emilmont 1:fdd22bb7aa52 371 */
emilmont 1:fdd22bb7aa52 372
emilmont 1:fdd22bb7aa52 373 void arm_float_to_q29 (float *pIn, q31_t * pOut,
emilmont 1:fdd22bb7aa52 374 uint32_t numSamples)
emilmont 1:fdd22bb7aa52 375 {
emilmont 1:fdd22bb7aa52 376 uint32_t i;
emilmont 1:fdd22bb7aa52 377
emilmont 1:fdd22bb7aa52 378 for (i = 0; i < numSamples; i++)
emilmont 1:fdd22bb7aa52 379 {
emilmont 1:fdd22bb7aa52 380 /* 1073741824.0f corresponds to pow(2, 30) */
emilmont 1:fdd22bb7aa52 381 pOut[i] = (q31_t) (pIn[i] * 536870912.0f);
emilmont 1:fdd22bb7aa52 382
emilmont 1:fdd22bb7aa52 383 pOut[i] += pIn[i] > 0 ? 0.5 : -0.5;
emilmont 1:fdd22bb7aa52 384
emilmont 1:fdd22bb7aa52 385 if (pIn[i] == (float) 4.0)
emilmont 1:fdd22bb7aa52 386 {
emilmont 1:fdd22bb7aa52 387 pOut[i] = 0x7FFFFFFF;
emilmont 1:fdd22bb7aa52 388 }
emilmont 1:fdd22bb7aa52 389 }
emilmont 1:fdd22bb7aa52 390 }
emilmont 1:fdd22bb7aa52 391
emilmont 1:fdd22bb7aa52 392
emilmont 1:fdd22bb7aa52 393 /**
emilmont 1:fdd22bb7aa52 394 * @brief Converts float to fixed q28 format
emilmont 1:fdd22bb7aa52 395 * @param uint32_t number of samples in the buffer
emilmont 1:fdd22bb7aa52 396 * @return none
emilmont 1:fdd22bb7aa52 397 * The function converts floating point values to fixed point values
emilmont 1:fdd22bb7aa52 398 */
emilmont 1:fdd22bb7aa52 399
emilmont 1:fdd22bb7aa52 400 void arm_float_to_q28 (float *pIn, q31_t * pOut,
emilmont 1:fdd22bb7aa52 401 uint32_t numSamples)
emilmont 1:fdd22bb7aa52 402 {
emilmont 1:fdd22bb7aa52 403 uint32_t i;
emilmont 1:fdd22bb7aa52 404
emilmont 1:fdd22bb7aa52 405 for (i = 0; i < numSamples; i++)
emilmont 1:fdd22bb7aa52 406 {
emilmont 1:fdd22bb7aa52 407 /* 268435456.0f corresponds to pow(2, 28) */
emilmont 1:fdd22bb7aa52 408 pOut[i] = (q31_t) (pIn[i] * 268435456.0f);
emilmont 1:fdd22bb7aa52 409
emilmont 1:fdd22bb7aa52 410 pOut[i] += pIn[i] > 0 ? 0.5 : -0.5;
emilmont 1:fdd22bb7aa52 411
emilmont 1:fdd22bb7aa52 412 if (pIn[i] == (float) 8.0)
emilmont 1:fdd22bb7aa52 413 {
emilmont 1:fdd22bb7aa52 414 pOut[i] = 0x7FFFFFFF;
emilmont 1:fdd22bb7aa52 415 }
emilmont 1:fdd22bb7aa52 416 }
emilmont 1:fdd22bb7aa52 417 }
emilmont 1:fdd22bb7aa52 418
emilmont 1:fdd22bb7aa52 419 /**
emilmont 1:fdd22bb7aa52 420 * @brief Clip the float values to +/- 1
emilmont 1:fdd22bb7aa52 421 * @param pIn input buffer
emilmont 1:fdd22bb7aa52 422 * @param numSamples number of samples in the buffer
emilmont 1:fdd22bb7aa52 423 * @return none
emilmont 1:fdd22bb7aa52 424 * The function converts floating point values to fixed point values
emilmont 1:fdd22bb7aa52 425 */
emilmont 1:fdd22bb7aa52 426
emilmont 1:fdd22bb7aa52 427 void arm_clip_f32 (float *pIn, uint32_t numSamples)
emilmont 1:fdd22bb7aa52 428 {
emilmont 1:fdd22bb7aa52 429 uint32_t i;
emilmont 1:fdd22bb7aa52 430
emilmont 1:fdd22bb7aa52 431 for (i = 0; i < numSamples; i++)
emilmont 1:fdd22bb7aa52 432 {
emilmont 1:fdd22bb7aa52 433 if(pIn[i] > 1.0f)
emilmont 1:fdd22bb7aa52 434 {
emilmont 1:fdd22bb7aa52 435 pIn[i] = 1.0;
emilmont 1:fdd22bb7aa52 436 }
emilmont 1:fdd22bb7aa52 437 else if( pIn[i] < -1.0f)
emilmont 1:fdd22bb7aa52 438 {
emilmont 1:fdd22bb7aa52 439 pIn[i] = -1.0;
emilmont 1:fdd22bb7aa52 440 }
emilmont 1:fdd22bb7aa52 441
emilmont 1:fdd22bb7aa52 442 }
emilmont 1:fdd22bb7aa52 443 }
emilmont 1:fdd22bb7aa52 444
emilmont 1:fdd22bb7aa52 445
emilmont 1:fdd22bb7aa52 446
emilmont 1:fdd22bb7aa52 447