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Dependencies:   4DGL-uLCD-SE LSM9DS1_Library-KVS MBed_Adafruit-GPS-Library PinDetect X_NUCLEO_53L0A1 mbed-rtos mbed

algorithm/algorithm.cpp@1:abc522e41d63, 2017-12-14 (annotated)

Committer:
ksastry3
Date:
Thu Dec 14 07:21:52 2017 +0000
Revision:
1:abc522e41d63
Final Version 12/14/2017 by Kartik V. Sastry

Who changed what in which revision?

UserRevisionLine numberNew contents of line
ksastry3 1:abc522e41d63 1 /** \file algorithm.cpp ******************************************************
ksastry3 1:abc522e41d63 2 *
ksastry3 1:abc522e41d63 3 * Project: MAXREFDES117#
ksastry3 1:abc522e41d63 4 * Filename: algorithm.cpp
ksastry3 1:abc522e41d63 5 * Description: This module calculates the heart rate/SpO2 level
ksastry3 1:abc522e41d63 6 *
ksastry3 1:abc522e41d63 7 *
ksastry3 1:abc522e41d63 8 * --------------------------------------------------------------------
ksastry3 1:abc522e41d63 9 *
ksastry3 1:abc522e41d63 10 * This code follows the following naming conventions:
ksastry3 1:abc522e41d63 11 *
ksastry3 1:abc522e41d63 12 * char ch_pmod_value
ksastry3 1:abc522e41d63 13 * char (array) s_pmod_s_string[16]
ksastry3 1:abc522e41d63 14 * float f_pmod_value
ksastry3 1:abc522e41d63 15 * int32_t n_pmod_value
ksastry3 1:abc522e41d63 16 * int32_t (array) an_pmod_value[16]
ksastry3 1:abc522e41d63 17 * int16_t w_pmod_value
ksastry3 1:abc522e41d63 18 * int16_t (array) aw_pmod_value[16]
ksastry3 1:abc522e41d63 19 * uint16_t uw_pmod_value
ksastry3 1:abc522e41d63 20 * uint16_t (array) auw_pmod_value[16]
ksastry3 1:abc522e41d63 21 * uint8_t uch_pmod_value
ksastry3 1:abc522e41d63 22 * uint8_t (array) auch_pmod_buffer[16]
ksastry3 1:abc522e41d63 23 * uint32_t un_pmod_value
ksastry3 1:abc522e41d63 24 * int32_t * pn_pmod_value
ksastry3 1:abc522e41d63 25 *
ksastry3 1:abc522e41d63 26 * ------------------------------------------------------------------------- */
ksastry3 1:abc522e41d63 27 /*******************************************************************************
ksastry3 1:abc522e41d63 28 * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
ksastry3 1:abc522e41d63 29 *
ksastry3 1:abc522e41d63 30 * Permission is hereby granted, free of charge, to any person obtaining a
ksastry3 1:abc522e41d63 31 * copy of this software and associated documentation files (the "Software"),
ksastry3 1:abc522e41d63 32 * to deal in the Software without restriction, including without limitation
ksastry3 1:abc522e41d63 33 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
ksastry3 1:abc522e41d63 34 * and/or sell copies of the Software, and to permit persons to whom the
ksastry3 1:abc522e41d63 35 * Software is furnished to do so, subject to the following conditions:
ksastry3 1:abc522e41d63 36 *
ksastry3 1:abc522e41d63 37 * The above copyright notice and this permission notice shall be included
ksastry3 1:abc522e41d63 38 * in all copies or substantial portions of the Software.
ksastry3 1:abc522e41d63 39 *
ksastry3 1:abc522e41d63 40 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
ksastry3 1:abc522e41d63 41 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
ksastry3 1:abc522e41d63 42 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
ksastry3 1:abc522e41d63 43 * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
ksastry3 1:abc522e41d63 44 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ksastry3 1:abc522e41d63 45 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
ksastry3 1:abc522e41d63 46 * OTHER DEALINGS IN THE SOFTWARE.
ksastry3 1:abc522e41d63 47 *
ksastry3 1:abc522e41d63 48 * Except as contained in this notice, the name of Maxim Integrated
ksastry3 1:abc522e41d63 49 * Products, Inc. shall not be used except as stated in the Maxim Integrated
ksastry3 1:abc522e41d63 50 * Products, Inc. Branding Policy.
ksastry3 1:abc522e41d63 51 *
ksastry3 1:abc522e41d63 52 * The mere transfer of this software does not imply any licenses
ksastry3 1:abc522e41d63 53 * of trade secrets, proprietary technology, copyrights, patents,
ksastry3 1:abc522e41d63 54 * trademarks, maskwork rights, or any other form of intellectual
ksastry3 1:abc522e41d63 55 * property whatsoever. Maxim Integrated Products, Inc. retains all
ksastry3 1:abc522e41d63 56 * ownership rights.
ksastry3 1:abc522e41d63 57 *******************************************************************************
ksastry3 1:abc522e41d63 58 */
ksastry3 1:abc522e41d63 59 #include "algorithm.h"
ksastry3 1:abc522e41d63 60 #include "mbed.h"
ksastry3 1:abc522e41d63 61
ksastry3 1:abc522e41d63 62 void maxim_heart_rate_and_oxygen_saturation(uint32_t *pun_ir_buffer, int32_t n_ir_buffer_length, uint32_t *pun_red_buffer, int32_t *pn_spo2, int8_t *pch_spo2_valid,
ksastry3 1:abc522e41d63 63 int32_t *pn_heart_rate, int8_t *pch_hr_valid)
ksastry3 1:abc522e41d63 64 /**
ksastry3 1:abc522e41d63 65 * \brief Calculate the heart rate and SpO2 level
ksastry3 1:abc522e41d63 66 * \par Details
ksastry3 1:abc522e41d63 67 * By detecting peaks of PPG cycle and corresponding AC/DC of red/infra-red signal, the ratio for the SPO2 is computed.
ksastry3 1:abc522e41d63 68 * Since this algorithm is aiming for Arm M0/M3. formaula for SPO2 did not achieve the accuracy due to register overflow.
ksastry3 1:abc522e41d63 69 * Thus, accurate SPO2 is precalculated and save longo uch_spo2_table[] per each ratio.
ksastry3 1:abc522e41d63 70 *
ksastry3 1:abc522e41d63 71 * \param[in] *pun_ir_buffer - IR sensor data buffer
ksastry3 1:abc522e41d63 72 * \param[in] n_ir_buffer_length - IR sensor data buffer length
ksastry3 1:abc522e41d63 73 * \param[in] *pun_red_buffer - Red sensor data buffer
ksastry3 1:abc522e41d63 74 * \param[out] *pn_spo2 - Calculated SpO2 value
ksastry3 1:abc522e41d63 75 * \param[out] *pch_spo2_valid - 1 if the calculated SpO2 value is valid
ksastry3 1:abc522e41d63 76 * \param[out] *pn_heart_rate - Calculated heart rate value
ksastry3 1:abc522e41d63 77 * \param[out] *pch_hr_valid - 1 if the calculated heart rate value is valid
ksastry3 1:abc522e41d63 78 *
ksastry3 1:abc522e41d63 79 * \retval None
ksastry3 1:abc522e41d63 80 */
ksastry3 1:abc522e41d63 81 {
ksastry3 1:abc522e41d63 82 uint32_t un_ir_mean ,un_only_once ;
ksastry3 1:abc522e41d63 83 int32_t k ,n_i_ratio_count;
ksastry3 1:abc522e41d63 84 int32_t i, s, m, n_exact_ir_valley_locs_count ,n_middle_idx;
ksastry3 1:abc522e41d63 85 int32_t n_th1, n_npks,n_c_min;
ksastry3 1:abc522e41d63 86 int32_t an_ir_valley_locs[15] ;
ksastry3 1:abc522e41d63 87 int32_t an_exact_ir_valley_locs[15] ;
ksastry3 1:abc522e41d63 88 int32_t an_dx_peak_locs[15] ;
ksastry3 1:abc522e41d63 89 int32_t n_peak_interval_sum;
ksastry3 1:abc522e41d63 90
ksastry3 1:abc522e41d63 91 int32_t n_y_ac, n_x_ac;
ksastry3 1:abc522e41d63 92 int32_t n_spo2_calc;
ksastry3 1:abc522e41d63 93 int32_t n_y_dc_max, n_x_dc_max;
ksastry3 1:abc522e41d63 94 int32_t n_y_dc_max_idx, n_x_dc_max_idx;
ksastry3 1:abc522e41d63 95 int32_t an_ratio[5],n_ratio_average;
ksastry3 1:abc522e41d63 96 int32_t n_nume, n_denom ;
ksastry3 1:abc522e41d63 97 // remove DC of ir signal
ksastry3 1:abc522e41d63 98 un_ir_mean =0;
ksastry3 1:abc522e41d63 99 for (k=0 ; k<n_ir_buffer_length ; k++ ) un_ir_mean += pun_ir_buffer[k] ;
ksastry3 1:abc522e41d63 100 un_ir_mean =un_ir_mean/n_ir_buffer_length ;
ksastry3 1:abc522e41d63 101 for (k=0 ; k<n_ir_buffer_length ; k++ ) an_x[k] = pun_ir_buffer[k] - un_ir_mean ;
ksastry3 1:abc522e41d63 102
ksastry3 1:abc522e41d63 103 // 4 pt Moving Average
ksastry3 1:abc522e41d63 104 for(k=0; k< BUFFER_SIZE-MA4_SIZE; k++){
ksastry3 1:abc522e41d63 105 n_denom= ( an_x[k]+an_x[k+1]+ an_x[k+2]+ an_x[k+3]);
ksastry3 1:abc522e41d63 106 an_x[k]= n_denom/(int32_t)4;
ksastry3 1:abc522e41d63 107 }
ksastry3 1:abc522e41d63 108
ksastry3 1:abc522e41d63 109 // get difference of smoothed IR signal
ksastry3 1:abc522e41d63 110
ksastry3 1:abc522e41d63 111 for( k=0; k<BUFFER_SIZE-MA4_SIZE-1; k++)
ksastry3 1:abc522e41d63 112 an_dx[k]= (an_x[k+1]- an_x[k]);
ksastry3 1:abc522e41d63 113
ksastry3 1:abc522e41d63 114 // 2-pt Moving Average to an_dx
ksastry3 1:abc522e41d63 115 for(k=0; k< BUFFER_SIZE-MA4_SIZE-2; k++){
ksastry3 1:abc522e41d63 116 an_dx[k] = ( an_dx[k]+an_dx[k+1])/2 ;
ksastry3 1:abc522e41d63 117 }
ksastry3 1:abc522e41d63 118
ksastry3 1:abc522e41d63 119 // hamming window
ksastry3 1:abc522e41d63 120 // flip wave form so that we can detect valley with peak detector
ksastry3 1:abc522e41d63 121 for ( i=0 ; i<BUFFER_SIZE-HAMMING_SIZE-MA4_SIZE-2 ;i++){
ksastry3 1:abc522e41d63 122 s= 0;
ksastry3 1:abc522e41d63 123 for( k=i; k<i+ HAMMING_SIZE ;k++){
ksastry3 1:abc522e41d63 124 s -= an_dx[k] *auw_hamm[k-i] ;
ksastry3 1:abc522e41d63 125 }
ksastry3 1:abc522e41d63 126 an_dx[i]= s/ (int32_t)1146; // divide by sum of auw_hamm
ksastry3 1:abc522e41d63 127 }
ksastry3 1:abc522e41d63 128
ksastry3 1:abc522e41d63 129
ksastry3 1:abc522e41d63 130 n_th1=0; // threshold calculation
ksastry3 1:abc522e41d63 131 for ( k=0 ; k<BUFFER_SIZE-HAMMING_SIZE ;k++){
ksastry3 1:abc522e41d63 132 n_th1 += ((an_dx[k]>0)? an_dx[k] : ((int32_t)0-an_dx[k])) ;
ksastry3 1:abc522e41d63 133 }
ksastry3 1:abc522e41d63 134 n_th1= n_th1/ ( BUFFER_SIZE-HAMMING_SIZE);
ksastry3 1:abc522e41d63 135 // peak location is acutally index for sharpest location of raw signal since we flipped the signal
ksastry3 1:abc522e41d63 136 maxim_find_peaks( an_dx_peak_locs, &n_npks, an_dx, BUFFER_SIZE-HAMMING_SIZE, n_th1, 8, 5 );//peak_height, peak_distance, max_num_peaks
ksastry3 1:abc522e41d63 137
ksastry3 1:abc522e41d63 138 n_peak_interval_sum =0;
ksastry3 1:abc522e41d63 139 if (n_npks>=2){
ksastry3 1:abc522e41d63 140 for (k=1; k<n_npks; k++)
ksastry3 1:abc522e41d63 141 n_peak_interval_sum += (an_dx_peak_locs[k]-an_dx_peak_locs[k -1]);
ksastry3 1:abc522e41d63 142 n_peak_interval_sum=n_peak_interval_sum/(n_npks-1);
ksastry3 1:abc522e41d63 143 *pn_heart_rate=(int32_t)(6000/n_peak_interval_sum);// beats per minutes
ksastry3 1:abc522e41d63 144 *pch_hr_valid = 1;
ksastry3 1:abc522e41d63 145 }
ksastry3 1:abc522e41d63 146 else {
ksastry3 1:abc522e41d63 147 *pn_heart_rate = -999;
ksastry3 1:abc522e41d63 148 *pch_hr_valid = 0;
ksastry3 1:abc522e41d63 149 }
ksastry3 1:abc522e41d63 150
ksastry3 1:abc522e41d63 151 for ( k=0 ; k<n_npks ;k++)
ksastry3 1:abc522e41d63 152 an_ir_valley_locs[k]=an_dx_peak_locs[k]+HAMMING_SIZE/2;
ksastry3 1:abc522e41d63 153
ksastry3 1:abc522e41d63 154
ksastry3 1:abc522e41d63 155 // raw value : RED(=y) and IR(=X)
ksastry3 1:abc522e41d63 156 // we need to assess DC and AC value of ir and red PPG.
ksastry3 1:abc522e41d63 157 for (k=0 ; k<n_ir_buffer_length ; k++ ) {
ksastry3 1:abc522e41d63 158 an_x[k] = pun_ir_buffer[k] ;
ksastry3 1:abc522e41d63 159 an_y[k] = pun_red_buffer[k] ;
ksastry3 1:abc522e41d63 160 }
ksastry3 1:abc522e41d63 161
ksastry3 1:abc522e41d63 162 // find precise min near an_ir_valley_locs
ksastry3 1:abc522e41d63 163 n_exact_ir_valley_locs_count =0;
ksastry3 1:abc522e41d63 164 for(k=0 ; k<n_npks ;k++){
ksastry3 1:abc522e41d63 165 un_only_once =1;
ksastry3 1:abc522e41d63 166 m=an_ir_valley_locs[k];
ksastry3 1:abc522e41d63 167 n_c_min= 16777216;//2^24;
ksastry3 1:abc522e41d63 168 if (m+5 < BUFFER_SIZE-HAMMING_SIZE && m-5 >0){
ksastry3 1:abc522e41d63 169 for(i= m-5;i<m+5; i++)
ksastry3 1:abc522e41d63 170 if (an_x[i]<n_c_min){
ksastry3 1:abc522e41d63 171 if (un_only_once >0){
ksastry3 1:abc522e41d63 172 un_only_once =0;
ksastry3 1:abc522e41d63 173 }
ksastry3 1:abc522e41d63 174 n_c_min= an_x[i] ;
ksastry3 1:abc522e41d63 175 an_exact_ir_valley_locs[k]=i;
ksastry3 1:abc522e41d63 176 }
ksastry3 1:abc522e41d63 177 if (un_only_once ==0)
ksastry3 1:abc522e41d63 178 n_exact_ir_valley_locs_count ++ ;
ksastry3 1:abc522e41d63 179 }
ksastry3 1:abc522e41d63 180 }
ksastry3 1:abc522e41d63 181 if (n_exact_ir_valley_locs_count <2 ){
ksastry3 1:abc522e41d63 182 *pn_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range
ksastry3 1:abc522e41d63 183 *pch_spo2_valid = 0;
ksastry3 1:abc522e41d63 184 return;
ksastry3 1:abc522e41d63 185 }
ksastry3 1:abc522e41d63 186 // 4 pt MA
ksastry3 1:abc522e41d63 187 for(k=0; k< BUFFER_SIZE-MA4_SIZE; k++){
ksastry3 1:abc522e41d63 188 an_x[k]=( an_x[k]+an_x[k+1]+ an_x[k+2]+ an_x[k+3])/(int32_t)4;
ksastry3 1:abc522e41d63 189 an_y[k]=( an_y[k]+an_y[k+1]+ an_y[k+2]+ an_y[k+3])/(int32_t)4;
ksastry3 1:abc522e41d63 190 }
ksastry3 1:abc522e41d63 191
ksastry3 1:abc522e41d63 192 //using an_exact_ir_valley_locs , find ir-red DC andir-red AC for SPO2 calibration ratio
ksastry3 1:abc522e41d63 193 //finding AC/DC maximum of raw ir * red between two valley locations
ksastry3 1:abc522e41d63 194 n_ratio_average =0;
ksastry3 1:abc522e41d63 195 n_i_ratio_count =0;
ksastry3 1:abc522e41d63 196
ksastry3 1:abc522e41d63 197 for(k=0; k< 5; k++) an_ratio[k]=0;
ksastry3 1:abc522e41d63 198 for (k=0; k< n_exact_ir_valley_locs_count; k++){
ksastry3 1:abc522e41d63 199 if (an_exact_ir_valley_locs[k] > BUFFER_SIZE ){
ksastry3 1:abc522e41d63 200 *pn_spo2 = -999 ; // do not use SPO2 since valley loc is out of range
ksastry3 1:abc522e41d63 201 *pch_spo2_valid = 0;
ksastry3 1:abc522e41d63 202 return;
ksastry3 1:abc522e41d63 203 }
ksastry3 1:abc522e41d63 204 }
ksastry3 1:abc522e41d63 205 // find max between two valley locations
ksastry3 1:abc522e41d63 206 // and use ratio betwen AC compoent of Ir & Red and DC compoent of Ir & Red for SPO2
ksastry3 1:abc522e41d63 207
ksastry3 1:abc522e41d63 208 for (k=0; k< n_exact_ir_valley_locs_count-1; k++){
ksastry3 1:abc522e41d63 209 n_y_dc_max= -16777216 ;
ksastry3 1:abc522e41d63 210 n_x_dc_max= - 16777216;
ksastry3 1:abc522e41d63 211 if (an_exact_ir_valley_locs[k+1]-an_exact_ir_valley_locs[k] >10){
ksastry3 1:abc522e41d63 212 for (i=an_exact_ir_valley_locs[k]; i< an_exact_ir_valley_locs[k+1]; i++){
ksastry3 1:abc522e41d63 213 if (an_x[i]> n_x_dc_max) {n_x_dc_max =an_x[i];n_x_dc_max_idx =i; }
ksastry3 1:abc522e41d63 214 if (an_y[i]> n_y_dc_max) {n_y_dc_max =an_y[i];n_y_dc_max_idx=i;}
ksastry3 1:abc522e41d63 215 }
ksastry3 1:abc522e41d63 216 n_y_ac= (an_y[an_exact_ir_valley_locs[k+1]] - an_y[an_exact_ir_valley_locs[k] ] )*(n_y_dc_max_idx -an_exact_ir_valley_locs[k]); //red
ksastry3 1:abc522e41d63 217 n_y_ac= an_y[an_exact_ir_valley_locs[k]] + n_y_ac/ (an_exact_ir_valley_locs[k+1] - an_exact_ir_valley_locs[k]) ;
ksastry3 1:abc522e41d63 218
ksastry3 1:abc522e41d63 219
ksastry3 1:abc522e41d63 220 n_y_ac= an_y[n_y_dc_max_idx] - n_y_ac; // subracting linear DC compoenents from raw
ksastry3 1:abc522e41d63 221 n_x_ac= (an_x[an_exact_ir_valley_locs[k+1]] - an_x[an_exact_ir_valley_locs[k] ] )*(n_x_dc_max_idx -an_exact_ir_valley_locs[k]); // ir
ksastry3 1:abc522e41d63 222 n_x_ac= an_x[an_exact_ir_valley_locs[k]] + n_x_ac/ (an_exact_ir_valley_locs[k+1] - an_exact_ir_valley_locs[k]);
ksastry3 1:abc522e41d63 223 n_x_ac= an_x[n_y_dc_max_idx] - n_x_ac; // subracting linear DC compoenents from raw
ksastry3 1:abc522e41d63 224 n_nume=( n_y_ac *n_x_dc_max)>>7 ; //prepare X100 to preserve floating value
ksastry3 1:abc522e41d63 225 n_denom= ( n_x_ac *n_y_dc_max)>>7;
ksastry3 1:abc522e41d63 226 if (n_denom>0 && n_i_ratio_count <5 && n_nume != 0)
ksastry3 1:abc522e41d63 227 {
ksastry3 1:abc522e41d63 228 an_ratio[n_i_ratio_count]= (n_nume*100)/n_denom ; //formular is ( n_y_ac *n_x_dc_max) / ( n_x_ac *n_y_dc_max) ;
ksastry3 1:abc522e41d63 229 n_i_ratio_count++;
ksastry3 1:abc522e41d63 230 }
ksastry3 1:abc522e41d63 231 }
ksastry3 1:abc522e41d63 232 }
ksastry3 1:abc522e41d63 233
ksastry3 1:abc522e41d63 234 maxim_sort_ascend(an_ratio, n_i_ratio_count);
ksastry3 1:abc522e41d63 235 n_middle_idx= n_i_ratio_count/2;
ksastry3 1:abc522e41d63 236
ksastry3 1:abc522e41d63 237 if (n_middle_idx >1)
ksastry3 1:abc522e41d63 238 n_ratio_average =( an_ratio[n_middle_idx-1] +an_ratio[n_middle_idx])/2; // use median
ksastry3 1:abc522e41d63 239 else
ksastry3 1:abc522e41d63 240 n_ratio_average = an_ratio[n_middle_idx ];
ksastry3 1:abc522e41d63 241
ksastry3 1:abc522e41d63 242 if( n_ratio_average>2 && n_ratio_average <184){
ksastry3 1:abc522e41d63 243 n_spo2_calc= uch_spo2_table[n_ratio_average] ;
ksastry3 1:abc522e41d63 244 *pn_spo2 = n_spo2_calc ;
ksastry3 1:abc522e41d63 245 *pch_spo2_valid = 1;// float_SPO2 = -45.060*n_ratio_average* n_ratio_average/10000 + 30.354 *n_ratio_average/100 + 94.845 ; // for comparison with table
ksastry3 1:abc522e41d63 246 }
ksastry3 1:abc522e41d63 247 else{
ksastry3 1:abc522e41d63 248 *pn_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range
ksastry3 1:abc522e41d63 249 *pch_spo2_valid = 0;
ksastry3 1:abc522e41d63 250 }
ksastry3 1:abc522e41d63 251 }
ksastry3 1:abc522e41d63 252
ksastry3 1:abc522e41d63 253
ksastry3 1:abc522e41d63 254 void maxim_find_peaks(int32_t *pn_locs, int32_t *pn_npks, int32_t *pn_x, int32_t n_size, int32_t n_min_height, int32_t n_min_distance, int32_t n_max_num)
ksastry3 1:abc522e41d63 255 /**
ksastry3 1:abc522e41d63 256 * \brief Find peaks
ksastry3 1:abc522e41d63 257 * \par Details
ksastry3 1:abc522e41d63 258 * Find at most MAX_NUM peaks above MIN_HEIGHT separated by at least MIN_DISTANCE
ksastry3 1:abc522e41d63 259 *
ksastry3 1:abc522e41d63 260 * \retval None
ksastry3 1:abc522e41d63 261 */
ksastry3 1:abc522e41d63 262 {
ksastry3 1:abc522e41d63 263 maxim_peaks_above_min_height( pn_locs, pn_npks, pn_x, n_size, n_min_height );
ksastry3 1:abc522e41d63 264 maxim_remove_close_peaks( pn_locs, pn_npks, pn_x, n_min_distance );
ksastry3 1:abc522e41d63 265 *pn_npks = min( *pn_npks, n_max_num );
ksastry3 1:abc522e41d63 266 }
ksastry3 1:abc522e41d63 267
ksastry3 1:abc522e41d63 268 void maxim_peaks_above_min_height(int32_t *pn_locs, int32_t *pn_npks, int32_t *pn_x, int32_t n_size, int32_t n_min_height)
ksastry3 1:abc522e41d63 269 /**
ksastry3 1:abc522e41d63 270 * \brief Find peaks above n_min_height
ksastry3 1:abc522e41d63 271 * \par Details
ksastry3 1:abc522e41d63 272 * Find all peaks above MIN_HEIGHT
ksastry3 1:abc522e41d63 273 *
ksastry3 1:abc522e41d63 274 * \retval None
ksastry3 1:abc522e41d63 275 */
ksastry3 1:abc522e41d63 276 {
ksastry3 1:abc522e41d63 277 int32_t i = 1, n_width;
ksastry3 1:abc522e41d63 278 *pn_npks = 0;
ksastry3 1:abc522e41d63 279
ksastry3 1:abc522e41d63 280 while (i < n_size-1){
ksastry3 1:abc522e41d63 281 if (pn_x[i] > n_min_height && pn_x[i] > pn_x[i-1]){ // find left edge of potential peaks
ksastry3 1:abc522e41d63 282 n_width = 1;
ksastry3 1:abc522e41d63 283 while (i+n_width < n_size && pn_x[i] == pn_x[i+n_width]) // find flat peaks
ksastry3 1:abc522e41d63 284 n_width++;
ksastry3 1:abc522e41d63 285 if (pn_x[i] > pn_x[i+n_width] && (*pn_npks) < 15 ){ // find right edge of peaks
ksastry3 1:abc522e41d63 286 pn_locs[(*pn_npks)++] = i;
ksastry3 1:abc522e41d63 287 // for flat peaks, peak location is left edge
ksastry3 1:abc522e41d63 288 i += n_width+1;
ksastry3 1:abc522e41d63 289 }
ksastry3 1:abc522e41d63 290 else
ksastry3 1:abc522e41d63 291 i += n_width;
ksastry3 1:abc522e41d63 292 }
ksastry3 1:abc522e41d63 293 else
ksastry3 1:abc522e41d63 294 i++;
ksastry3 1:abc522e41d63 295 }
ksastry3 1:abc522e41d63 296 }
ksastry3 1:abc522e41d63 297
ksastry3 1:abc522e41d63 298
ksastry3 1:abc522e41d63 299 void maxim_remove_close_peaks(int32_t *pn_locs, int32_t *pn_npks, int32_t *pn_x, int32_t n_min_distance)
ksastry3 1:abc522e41d63 300 /**
ksastry3 1:abc522e41d63 301 * \brief Remove peaks
ksastry3 1:abc522e41d63 302 * \par Details
ksastry3 1:abc522e41d63 303 * Remove peaks separated by less than MIN_DISTANCE
ksastry3 1:abc522e41d63 304 *
ksastry3 1:abc522e41d63 305 * \retval None
ksastry3 1:abc522e41d63 306 */
ksastry3 1:abc522e41d63 307 {
ksastry3 1:abc522e41d63 308
ksastry3 1:abc522e41d63 309 int32_t i, j, n_old_npks, n_dist;
ksastry3 1:abc522e41d63 310
ksastry3 1:abc522e41d63 311 /* Order peaks from large to small */
ksastry3 1:abc522e41d63 312 maxim_sort_indices_descend( pn_x, pn_locs, *pn_npks );
ksastry3 1:abc522e41d63 313
ksastry3 1:abc522e41d63 314 for ( i = -1; i < *pn_npks; i++ ){
ksastry3 1:abc522e41d63 315 n_old_npks = *pn_npks;
ksastry3 1:abc522e41d63 316 *pn_npks = i+1;
ksastry3 1:abc522e41d63 317 for ( j = i+1; j < n_old_npks; j++ ){
ksastry3 1:abc522e41d63 318 n_dist = pn_locs[j] - ( i == -1 ? -1 : pn_locs[i] ); // lag-zero peak of autocorr is at index -1
ksastry3 1:abc522e41d63 319 if ( n_dist > n_min_distance || n_dist < -n_min_distance )
ksastry3 1:abc522e41d63 320 pn_locs[(*pn_npks)++] = pn_locs[j];
ksastry3 1:abc522e41d63 321 }
ksastry3 1:abc522e41d63 322 }
ksastry3 1:abc522e41d63 323
ksastry3 1:abc522e41d63 324 // Resort indices longo ascending order
ksastry3 1:abc522e41d63 325 maxim_sort_ascend( pn_locs, *pn_npks );
ksastry3 1:abc522e41d63 326 }
ksastry3 1:abc522e41d63 327
ksastry3 1:abc522e41d63 328 void maxim_sort_ascend(int32_t *pn_x,int32_t n_size)
ksastry3 1:abc522e41d63 329 /**
ksastry3 1:abc522e41d63 330 * \brief Sort array
ksastry3 1:abc522e41d63 331 * \par Details
ksastry3 1:abc522e41d63 332 * Sort array in ascending order (insertion sort algorithm)
ksastry3 1:abc522e41d63 333 *
ksastry3 1:abc522e41d63 334 * \retval None
ksastry3 1:abc522e41d63 335 */
ksastry3 1:abc522e41d63 336 {
ksastry3 1:abc522e41d63 337 int32_t i, j, n_temp;
ksastry3 1:abc522e41d63 338 for (i = 1; i < n_size; i++) {
ksastry3 1:abc522e41d63 339 n_temp = pn_x[i];
ksastry3 1:abc522e41d63 340 for (j = i; j > 0 && n_temp < pn_x[j-1]; j--)
ksastry3 1:abc522e41d63 341 pn_x[j] = pn_x[j-1];
ksastry3 1:abc522e41d63 342 pn_x[j] = n_temp;
ksastry3 1:abc522e41d63 343 }
ksastry3 1:abc522e41d63 344 }
ksastry3 1:abc522e41d63 345
ksastry3 1:abc522e41d63 346 void maxim_sort_indices_descend(int32_t *pn_x, int32_t *pn_indx, int32_t n_size)
ksastry3 1:abc522e41d63 347 /**
ksastry3 1:abc522e41d63 348 * \brief Sort indices
ksastry3 1:abc522e41d63 349 * \par Details
ksastry3 1:abc522e41d63 350 * Sort indices according to descending order (insertion sort algorithm)
ksastry3 1:abc522e41d63 351 *
ksastry3 1:abc522e41d63 352 * \retval None
ksastry3 1:abc522e41d63 353 */
ksastry3 1:abc522e41d63 354 {
ksastry3 1:abc522e41d63 355 int32_t i, j, n_temp;
ksastry3 1:abc522e41d63 356 for (i = 1; i < n_size; i++) {
ksastry3 1:abc522e41d63 357 n_temp = pn_indx[i];
ksastry3 1:abc522e41d63 358 for (j = i; j > 0 && pn_x[n_temp] > pn_x[pn_indx[j-1]]; j--)
ksastry3 1:abc522e41d63 359 pn_indx[j] = pn_indx[j-1];
ksastry3 1:abc522e41d63 360 pn_indx[j] = n_temp;
ksastry3 1:abc522e41d63 361 }
ksastry3 1:abc522e41d63 362 }
ksastry3 1:abc522e41d63 363