Junichi Katsu
心拍・酸素飽和度モニタモジュール MAXREFDES117から取得した心拍の値をシリアルコンソールに表示するプログラムです。
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microbit-component-display
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algorithm/algorithm.cpp@1:83ace7df2c63, 2018-04-16 (annotated)
- Committer:
- JKsoft_main
- Date:
- Mon Apr 16 16:52:36 2018 +0000
- Revision:
- 1:83ace7df2c63
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Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| JKsoft_main | 1:83ace7df2c63 | 1 | /** \file algorithm.cpp ****************************************************** |
| JKsoft_main | 1:83ace7df2c63 | 2 | * |
| JKsoft_main | 1:83ace7df2c63 | 3 | * Project: MAXREFDES117# |
| JKsoft_main | 1:83ace7df2c63 | 4 | * Filename: algorithm.cpp |
| JKsoft_main | 1:83ace7df2c63 | 5 | * Description: This module calculates the heart rate/SpO2 level |
| JKsoft_main | 1:83ace7df2c63 | 6 | * |
| JKsoft_main | 1:83ace7df2c63 | 7 | * |
| JKsoft_main | 1:83ace7df2c63 | 8 | * -------------------------------------------------------------------- |
| JKsoft_main | 1:83ace7df2c63 | 9 | * |
| JKsoft_main | 1:83ace7df2c63 | 10 | * This code follows the following naming conventions: |
| JKsoft_main | 1:83ace7df2c63 | 11 | * |
| JKsoft_main | 1:83ace7df2c63 | 12 | * char ch_pmod_value |
| JKsoft_main | 1:83ace7df2c63 | 13 | * char (array) s_pmod_s_string[16] |
| JKsoft_main | 1:83ace7df2c63 | 14 | * float f_pmod_value |
| JKsoft_main | 1:83ace7df2c63 | 15 | * int32_t n_pmod_value |
| JKsoft_main | 1:83ace7df2c63 | 16 | * int32_t (array) an_pmod_value[16] |
| JKsoft_main | 1:83ace7df2c63 | 17 | * int16_t w_pmod_value |
| JKsoft_main | 1:83ace7df2c63 | 18 | * int16_t (array) aw_pmod_value[16] |
| JKsoft_main | 1:83ace7df2c63 | 19 | * uint16_t uw_pmod_value |
| JKsoft_main | 1:83ace7df2c63 | 20 | * uint16_t (array) auw_pmod_value[16] |
| JKsoft_main | 1:83ace7df2c63 | 21 | * uint8_t uch_pmod_value |
| JKsoft_main | 1:83ace7df2c63 | 22 | * uint8_t (array) auch_pmod_buffer[16] |
| JKsoft_main | 1:83ace7df2c63 | 23 | * uint32_t un_pmod_value |
| JKsoft_main | 1:83ace7df2c63 | 24 | * int32_t * pn_pmod_value |
| JKsoft_main | 1:83ace7df2c63 | 25 | * |
| JKsoft_main | 1:83ace7df2c63 | 26 | * ------------------------------------------------------------------------- */ |
| JKsoft_main | 1:83ace7df2c63 | 27 | /******************************************************************************* |
| JKsoft_main | 1:83ace7df2c63 | 28 | * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved. |
| JKsoft_main | 1:83ace7df2c63 | 29 | * |
| JKsoft_main | 1:83ace7df2c63 | 30 | * Permission is hereby granted, free of charge, to any person obtaining a |
| JKsoft_main | 1:83ace7df2c63 | 31 | * copy of this software and associated documentation files (the "Software"), |
| JKsoft_main | 1:83ace7df2c63 | 32 | * to deal in the Software without restriction, including without limitation |
| JKsoft_main | 1:83ace7df2c63 | 33 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| JKsoft_main | 1:83ace7df2c63 | 34 | * and/or sell copies of the Software, and to permit persons to whom the |
| JKsoft_main | 1:83ace7df2c63 | 35 | * Software is furnished to do so, subject to the following conditions: |
| JKsoft_main | 1:83ace7df2c63 | 36 | * |
| JKsoft_main | 1:83ace7df2c63 | 37 | * The above copyright notice and this permission notice shall be included |
| JKsoft_main | 1:83ace7df2c63 | 38 | * in all copies or substantial portions of the Software. |
| JKsoft_main | 1:83ace7df2c63 | 39 | * |
| JKsoft_main | 1:83ace7df2c63 | 40 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
| JKsoft_main | 1:83ace7df2c63 | 41 | * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| JKsoft_main | 1:83ace7df2c63 | 42 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. |
| JKsoft_main | 1:83ace7df2c63 | 43 | * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES |
| JKsoft_main | 1:83ace7df2c63 | 44 | * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
| JKsoft_main | 1:83ace7df2c63 | 45 | * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
| JKsoft_main | 1:83ace7df2c63 | 46 | * OTHER DEALINGS IN THE SOFTWARE. |
| JKsoft_main | 1:83ace7df2c63 | 47 | * |
| JKsoft_main | 1:83ace7df2c63 | 48 | * Except as contained in this notice, the name of Maxim Integrated |
| JKsoft_main | 1:83ace7df2c63 | 49 | * Products, Inc. shall not be used except as stated in the Maxim Integrated |
| JKsoft_main | 1:83ace7df2c63 | 50 | * Products, Inc. Branding Policy. |
| JKsoft_main | 1:83ace7df2c63 | 51 | * |
| JKsoft_main | 1:83ace7df2c63 | 52 | * The mere transfer of this software does not imply any licenses |
| JKsoft_main | 1:83ace7df2c63 | 53 | * of trade secrets, proprietary technology, copyrights, patents, |
| JKsoft_main | 1:83ace7df2c63 | 54 | * trademarks, maskwork rights, or any other form of intellectual |
| JKsoft_main | 1:83ace7df2c63 | 55 | * property whatsoever. Maxim Integrated Products, Inc. retains all |
| JKsoft_main | 1:83ace7df2c63 | 56 | * ownership rights. |
| JKsoft_main | 1:83ace7df2c63 | 57 | ******************************************************************************* |
| JKsoft_main | 1:83ace7df2c63 | 58 | */ |
| JKsoft_main | 1:83ace7df2c63 | 59 | #include "algorithm.h" |
| JKsoft_main | 1:83ace7df2c63 | 60 | #include "mbed.h" |
| JKsoft_main | 1:83ace7df2c63 | 61 | |
| JKsoft_main | 1:83ace7df2c63 | 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, |
| JKsoft_main | 1:83ace7df2c63 | 63 | int32_t *pn_heart_rate, int8_t *pch_hr_valid) |
| JKsoft_main | 1:83ace7df2c63 | 64 | /** |
| JKsoft_main | 1:83ace7df2c63 | 65 | * \brief Calculate the heart rate and SpO2 level |
| JKsoft_main | 1:83ace7df2c63 | 66 | * \par Details |
| JKsoft_main | 1:83ace7df2c63 | 67 | * By detecting peaks of PPG cycle and corresponding AC/DC of red/infra-red signal, the ratio for the SPO2 is computed. |
| JKsoft_main | 1:83ace7df2c63 | 68 | * Since this algorithm is aiming for Arm M0/M3. formaula for SPO2 did not achieve the accuracy due to register overflow. |
| JKsoft_main | 1:83ace7df2c63 | 69 | * Thus, accurate SPO2 is precalculated and save longo uch_spo2_table[] per each ratio. |
| JKsoft_main | 1:83ace7df2c63 | 70 | * |
| JKsoft_main | 1:83ace7df2c63 | 71 | * \param[in] *pun_ir_buffer - IR sensor data buffer |
| JKsoft_main | 1:83ace7df2c63 | 72 | * \param[in] n_ir_buffer_length - IR sensor data buffer length |
| JKsoft_main | 1:83ace7df2c63 | 73 | * \param[in] *pun_red_buffer - Red sensor data buffer |
| JKsoft_main | 1:83ace7df2c63 | 74 | * \param[out] *pn_spo2 - Calculated SpO2 value |
| JKsoft_main | 1:83ace7df2c63 | 75 | * \param[out] *pch_spo2_valid - 1 if the calculated SpO2 value is valid |
| JKsoft_main | 1:83ace7df2c63 | 76 | * \param[out] *pn_heart_rate - Calculated heart rate value |
| JKsoft_main | 1:83ace7df2c63 | 77 | * \param[out] *pch_hr_valid - 1 if the calculated heart rate value is valid |
| JKsoft_main | 1:83ace7df2c63 | 78 | * |
| JKsoft_main | 1:83ace7df2c63 | 79 | * \retval None |
| JKsoft_main | 1:83ace7df2c63 | 80 | */ |
| JKsoft_main | 1:83ace7df2c63 | 81 | { |
| JKsoft_main | 1:83ace7df2c63 | 82 | uint32_t un_ir_mean ,un_only_once ; |
| JKsoft_main | 1:83ace7df2c63 | 83 | int32_t k ,n_i_ratio_count; |
| JKsoft_main | 1:83ace7df2c63 | 84 | int32_t i,s ,m, n_exact_ir_valley_locs_count ,n_middle_idx; |
| JKsoft_main | 1:83ace7df2c63 | 85 | int32_t n_th1, n_npks,n_c_min; |
| JKsoft_main | 1:83ace7df2c63 | 86 | int32_t an_ir_valley_locs[15] ; |
| JKsoft_main | 1:83ace7df2c63 | 87 | int32_t an_exact_ir_valley_locs[15] ; |
| JKsoft_main | 1:83ace7df2c63 | 88 | int32_t an_dx_peak_locs[15] ; |
| JKsoft_main | 1:83ace7df2c63 | 89 | int32_t n_peak_interval_sum; |
| JKsoft_main | 1:83ace7df2c63 | 90 | |
| JKsoft_main | 1:83ace7df2c63 | 91 | int32_t n_y_ac, n_x_ac; |
| JKsoft_main | 1:83ace7df2c63 | 92 | int32_t n_spo2_calc; |
| JKsoft_main | 1:83ace7df2c63 | 93 | int32_t n_y_dc_max, n_x_dc_max; |
| JKsoft_main | 1:83ace7df2c63 | 94 | int32_t n_y_dc_max_idx, n_x_dc_max_idx; |
| JKsoft_main | 1:83ace7df2c63 | 95 | int32_t an_ratio[5],n_ratio_average; |
| JKsoft_main | 1:83ace7df2c63 | 96 | int32_t n_nume, n_denom ; |
| JKsoft_main | 1:83ace7df2c63 | 97 | // remove DC of ir signal |
| JKsoft_main | 1:83ace7df2c63 | 98 | un_ir_mean =0; |
| JKsoft_main | 1:83ace7df2c63 | 99 | for (k=0 ; k<n_ir_buffer_length ; k++ ) un_ir_mean += pun_ir_buffer[k] ; |
| JKsoft_main | 1:83ace7df2c63 | 100 | un_ir_mean =un_ir_mean/n_ir_buffer_length ; |
| JKsoft_main | 1:83ace7df2c63 | 101 | for (k=0 ; k<n_ir_buffer_length ; k++ ) an_x[k] = pun_ir_buffer[k] - un_ir_mean ; |
| JKsoft_main | 1:83ace7df2c63 | 102 | |
| JKsoft_main | 1:83ace7df2c63 | 103 | // 4 pt Moving Average |
| JKsoft_main | 1:83ace7df2c63 | 104 | for(k=0; k< BUFFER_SIZE-MA4_SIZE; k++){ |
| JKsoft_main | 1:83ace7df2c63 | 105 | n_denom= ( an_x[k]+an_x[k+1]+ an_x[k+2]+ an_x[k+3]); |
| JKsoft_main | 1:83ace7df2c63 | 106 | an_x[k]= n_denom/(int32_t)4; |
| JKsoft_main | 1:83ace7df2c63 | 107 | } |
| JKsoft_main | 1:83ace7df2c63 | 108 | |
| JKsoft_main | 1:83ace7df2c63 | 109 | // get difference of smoothed IR signal |
| JKsoft_main | 1:83ace7df2c63 | 110 | |
| JKsoft_main | 1:83ace7df2c63 | 111 | for( k=0; k<BUFFER_SIZE-MA4_SIZE-1; k++) |
| JKsoft_main | 1:83ace7df2c63 | 112 | an_dx[k]= (an_x[k+1]- an_x[k]); |
| JKsoft_main | 1:83ace7df2c63 | 113 | |
| JKsoft_main | 1:83ace7df2c63 | 114 | // 2-pt Moving Average to an_dx |
| JKsoft_main | 1:83ace7df2c63 | 115 | for(k=0; k< BUFFER_SIZE-MA4_SIZE-2; k++){ |
| JKsoft_main | 1:83ace7df2c63 | 116 | an_dx[k] = ( an_dx[k]+an_dx[k+1])/2 ; |
| JKsoft_main | 1:83ace7df2c63 | 117 | } |
| JKsoft_main | 1:83ace7df2c63 | 118 | |
| JKsoft_main | 1:83ace7df2c63 | 119 | // hamming window |
| JKsoft_main | 1:83ace7df2c63 | 120 | // flip wave form so that we can detect valley with peak detector |
| JKsoft_main | 1:83ace7df2c63 | 121 | for ( i=0 ; i<BUFFER_SIZE-HAMMING_SIZE-MA4_SIZE-2 ;i++){ |
| JKsoft_main | 1:83ace7df2c63 | 122 | s= 0; |
| JKsoft_main | 1:83ace7df2c63 | 123 | for( k=i; k<i+ HAMMING_SIZE ;k++){ |
| JKsoft_main | 1:83ace7df2c63 | 124 | s -= an_dx[k] *auw_hamm[k-i] ; |
| JKsoft_main | 1:83ace7df2c63 | 125 | } |
| JKsoft_main | 1:83ace7df2c63 | 126 | an_dx[i]= s/ (int32_t)1146; // divide by sum of auw_hamm |
| JKsoft_main | 1:83ace7df2c63 | 127 | } |
| JKsoft_main | 1:83ace7df2c63 | 128 | |
| JKsoft_main | 1:83ace7df2c63 | 129 | |
| JKsoft_main | 1:83ace7df2c63 | 130 | n_th1=0; // threshold calculation |
| JKsoft_main | 1:83ace7df2c63 | 131 | for ( k=0 ; k<BUFFER_SIZE-HAMMING_SIZE ;k++){ |
| JKsoft_main | 1:83ace7df2c63 | 132 | n_th1 += ((an_dx[k]>0)? an_dx[k] : ((int32_t)0-an_dx[k])) ; |
| JKsoft_main | 1:83ace7df2c63 | 133 | } |
| JKsoft_main | 1:83ace7df2c63 | 134 | n_th1= n_th1/ ( BUFFER_SIZE-HAMMING_SIZE); |
| JKsoft_main | 1:83ace7df2c63 | 135 | // peak location is acutally index for sharpest location of raw signal since we flipped the signal |
| JKsoft_main | 1:83ace7df2c63 | 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 |
| JKsoft_main | 1:83ace7df2c63 | 137 | |
| JKsoft_main | 1:83ace7df2c63 | 138 | n_peak_interval_sum =0; |
| JKsoft_main | 1:83ace7df2c63 | 139 | if (n_npks>=2){ |
| JKsoft_main | 1:83ace7df2c63 | 140 | for (k=1; k<n_npks; k++) |
| JKsoft_main | 1:83ace7df2c63 | 141 | n_peak_interval_sum += (an_dx_peak_locs[k]-an_dx_peak_locs[k -1]); |
| JKsoft_main | 1:83ace7df2c63 | 142 | n_peak_interval_sum=n_peak_interval_sum/(n_npks-1); |
| JKsoft_main | 1:83ace7df2c63 | 143 | *pn_heart_rate=(int32_t)(6000/n_peak_interval_sum);// beats per minutes |
| JKsoft_main | 1:83ace7df2c63 | 144 | *pch_hr_valid = 1; |
| JKsoft_main | 1:83ace7df2c63 | 145 | } |
| JKsoft_main | 1:83ace7df2c63 | 146 | else { |
| JKsoft_main | 1:83ace7df2c63 | 147 | *pn_heart_rate = -999; |
| JKsoft_main | 1:83ace7df2c63 | 148 | *pch_hr_valid = 0; |
| JKsoft_main | 1:83ace7df2c63 | 149 | } |
| JKsoft_main | 1:83ace7df2c63 | 150 | |
| JKsoft_main | 1:83ace7df2c63 | 151 | for ( k=0 ; k<n_npks ;k++) |
| JKsoft_main | 1:83ace7df2c63 | 152 | an_ir_valley_locs[k]=an_dx_peak_locs[k]+HAMMING_SIZE/2; |
| JKsoft_main | 1:83ace7df2c63 | 153 | |
| JKsoft_main | 1:83ace7df2c63 | 154 | |
| JKsoft_main | 1:83ace7df2c63 | 155 | // raw value : RED(=y) and IR(=X) |
| JKsoft_main | 1:83ace7df2c63 | 156 | // we need to assess DC and AC value of ir and red PPG. |
| JKsoft_main | 1:83ace7df2c63 | 157 | for (k=0 ; k<n_ir_buffer_length ; k++ ) { |
| JKsoft_main | 1:83ace7df2c63 | 158 | an_x[k] = pun_ir_buffer[k] ; |
| JKsoft_main | 1:83ace7df2c63 | 159 | an_y[k] = pun_red_buffer[k] ; |
| JKsoft_main | 1:83ace7df2c63 | 160 | } |
| JKsoft_main | 1:83ace7df2c63 | 161 | |
| JKsoft_main | 1:83ace7df2c63 | 162 | // find precise min near an_ir_valley_locs |
| JKsoft_main | 1:83ace7df2c63 | 163 | n_exact_ir_valley_locs_count =0; |
| JKsoft_main | 1:83ace7df2c63 | 164 | for(k=0 ; k<n_npks ;k++){ |
| JKsoft_main | 1:83ace7df2c63 | 165 | un_only_once =1; |
| JKsoft_main | 1:83ace7df2c63 | 166 | m=an_ir_valley_locs[k]; |
| JKsoft_main | 1:83ace7df2c63 | 167 | n_c_min= 16777216;//2^24; |
| JKsoft_main | 1:83ace7df2c63 | 168 | if (m+5 < BUFFER_SIZE-HAMMING_SIZE && m-5 >0){ |
| JKsoft_main | 1:83ace7df2c63 | 169 | for(i= m-5;i<m+5; i++) |
| JKsoft_main | 1:83ace7df2c63 | 170 | if (an_x[i]<n_c_min){ |
| JKsoft_main | 1:83ace7df2c63 | 171 | if (un_only_once >0){ |
| JKsoft_main | 1:83ace7df2c63 | 172 | un_only_once =0; |
| JKsoft_main | 1:83ace7df2c63 | 173 | } |
| JKsoft_main | 1:83ace7df2c63 | 174 | n_c_min= an_x[i] ; |
| JKsoft_main | 1:83ace7df2c63 | 175 | an_exact_ir_valley_locs[k]=i; |
| JKsoft_main | 1:83ace7df2c63 | 176 | } |
| JKsoft_main | 1:83ace7df2c63 | 177 | if (un_only_once ==0) |
| JKsoft_main | 1:83ace7df2c63 | 178 | n_exact_ir_valley_locs_count ++ ; |
| JKsoft_main | 1:83ace7df2c63 | 179 | } |
| JKsoft_main | 1:83ace7df2c63 | 180 | } |
| JKsoft_main | 1:83ace7df2c63 | 181 | if (n_exact_ir_valley_locs_count <2 ){ |
| JKsoft_main | 1:83ace7df2c63 | 182 | *pn_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range |
| JKsoft_main | 1:83ace7df2c63 | 183 | *pch_spo2_valid = 0; |
| JKsoft_main | 1:83ace7df2c63 | 184 | return; |
| JKsoft_main | 1:83ace7df2c63 | 185 | } |
| JKsoft_main | 1:83ace7df2c63 | 186 | // 4 pt MA |
| JKsoft_main | 1:83ace7df2c63 | 187 | for(k=0; k< BUFFER_SIZE-MA4_SIZE; k++){ |
| JKsoft_main | 1:83ace7df2c63 | 188 | an_x[k]=( an_x[k]+an_x[k+1]+ an_x[k+2]+ an_x[k+3])/(int32_t)4; |
| JKsoft_main | 1:83ace7df2c63 | 189 | an_y[k]=( an_y[k]+an_y[k+1]+ an_y[k+2]+ an_y[k+3])/(int32_t)4; |
| JKsoft_main | 1:83ace7df2c63 | 190 | } |
| JKsoft_main | 1:83ace7df2c63 | 191 | |
| JKsoft_main | 1:83ace7df2c63 | 192 | //using an_exact_ir_valley_locs , find ir-red DC andir-red AC for SPO2 calibration ratio |
| JKsoft_main | 1:83ace7df2c63 | 193 | //finding AC/DC maximum of raw ir * red between two valley locations |
| JKsoft_main | 1:83ace7df2c63 | 194 | n_ratio_average =0; |
| JKsoft_main | 1:83ace7df2c63 | 195 | n_i_ratio_count =0; |
| JKsoft_main | 1:83ace7df2c63 | 196 | |
| JKsoft_main | 1:83ace7df2c63 | 197 | for(k=0; k< 5; k++) an_ratio[k]=0; |
| JKsoft_main | 1:83ace7df2c63 | 198 | for (k=0; k< n_exact_ir_valley_locs_count; k++){ |
| JKsoft_main | 1:83ace7df2c63 | 199 | if (an_exact_ir_valley_locs[k] > BUFFER_SIZE ){ |
| JKsoft_main | 1:83ace7df2c63 | 200 | *pn_spo2 = -999 ; // do not use SPO2 since valley loc is out of range |
| JKsoft_main | 1:83ace7df2c63 | 201 | *pch_spo2_valid = 0; |
| JKsoft_main | 1:83ace7df2c63 | 202 | return; |
| JKsoft_main | 1:83ace7df2c63 | 203 | } |
| JKsoft_main | 1:83ace7df2c63 | 204 | } |
| JKsoft_main | 1:83ace7df2c63 | 205 | // find max between two valley locations |
| JKsoft_main | 1:83ace7df2c63 | 206 | // and use ratio betwen AC compoent of Ir & Red and DC compoent of Ir & Red for SPO2 |
| JKsoft_main | 1:83ace7df2c63 | 207 | |
| JKsoft_main | 1:83ace7df2c63 | 208 | for (k=0; k< n_exact_ir_valley_locs_count-1; k++){ |
| JKsoft_main | 1:83ace7df2c63 | 209 | n_y_dc_max= -16777216 ; |
| JKsoft_main | 1:83ace7df2c63 | 210 | n_x_dc_max= - 16777216; |
| JKsoft_main | 1:83ace7df2c63 | 211 | if (an_exact_ir_valley_locs[k+1]-an_exact_ir_valley_locs[k] >10){ |
| JKsoft_main | 1:83ace7df2c63 | 212 | for (i=an_exact_ir_valley_locs[k]; i< an_exact_ir_valley_locs[k+1]; i++){ |
| JKsoft_main | 1:83ace7df2c63 | 213 | if (an_x[i]> n_x_dc_max) {n_x_dc_max =an_x[i];n_x_dc_max_idx =i; } |
| JKsoft_main | 1:83ace7df2c63 | 214 | if (an_y[i]> n_y_dc_max) {n_y_dc_max =an_y[i];n_y_dc_max_idx=i;} |
| JKsoft_main | 1:83ace7df2c63 | 215 | } |
| JKsoft_main | 1:83ace7df2c63 | 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 |
| JKsoft_main | 1:83ace7df2c63 | 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]) ; |
| JKsoft_main | 1:83ace7df2c63 | 218 | |
| JKsoft_main | 1:83ace7df2c63 | 219 | |
| JKsoft_main | 1:83ace7df2c63 | 220 | n_y_ac= an_y[n_y_dc_max_idx] - n_y_ac; // subracting linear DC compoenents from raw |
| JKsoft_main | 1:83ace7df2c63 | 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 |
| JKsoft_main | 1:83ace7df2c63 | 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]); |
| JKsoft_main | 1:83ace7df2c63 | 223 | n_x_ac= an_x[n_y_dc_max_idx] - n_x_ac; // subracting linear DC compoenents from raw |
| JKsoft_main | 1:83ace7df2c63 | 224 | n_nume=( n_y_ac *n_x_dc_max)>>7 ; //prepare X100 to preserve floating value |
| JKsoft_main | 1:83ace7df2c63 | 225 | n_denom= ( n_x_ac *n_y_dc_max)>>7; |
| JKsoft_main | 1:83ace7df2c63 | 226 | if (n_denom>0 && n_i_ratio_count <5 && n_nume != 0) |
| JKsoft_main | 1:83ace7df2c63 | 227 | { |
| JKsoft_main | 1:83ace7df2c63 | 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) ; |
| JKsoft_main | 1:83ace7df2c63 | 229 | n_i_ratio_count++; |
| JKsoft_main | 1:83ace7df2c63 | 230 | } |
| JKsoft_main | 1:83ace7df2c63 | 231 | } |
| JKsoft_main | 1:83ace7df2c63 | 232 | } |
| JKsoft_main | 1:83ace7df2c63 | 233 | |
| JKsoft_main | 1:83ace7df2c63 | 234 | maxim_sort_ascend(an_ratio, n_i_ratio_count); |
| JKsoft_main | 1:83ace7df2c63 | 235 | n_middle_idx= n_i_ratio_count/2; |
| JKsoft_main | 1:83ace7df2c63 | 236 | |
| JKsoft_main | 1:83ace7df2c63 | 237 | if (n_middle_idx >1) |
| JKsoft_main | 1:83ace7df2c63 | 238 | n_ratio_average =( an_ratio[n_middle_idx-1] +an_ratio[n_middle_idx])/2; // use median |
| JKsoft_main | 1:83ace7df2c63 | 239 | else |
| JKsoft_main | 1:83ace7df2c63 | 240 | n_ratio_average = an_ratio[n_middle_idx ]; |
| JKsoft_main | 1:83ace7df2c63 | 241 | |
| JKsoft_main | 1:83ace7df2c63 | 242 | if( n_ratio_average>2 && n_ratio_average <184){ |
| JKsoft_main | 1:83ace7df2c63 | 243 | n_spo2_calc= uch_spo2_table[n_ratio_average] ; |
| JKsoft_main | 1:83ace7df2c63 | 244 | *pn_spo2 = n_spo2_calc ; |
| JKsoft_main | 1:83ace7df2c63 | 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 |
| JKsoft_main | 1:83ace7df2c63 | 246 | } |
| JKsoft_main | 1:83ace7df2c63 | 247 | else{ |
| JKsoft_main | 1:83ace7df2c63 | 248 | *pn_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range |
| JKsoft_main | 1:83ace7df2c63 | 249 | *pch_spo2_valid = 0; |
| JKsoft_main | 1:83ace7df2c63 | 250 | } |
| JKsoft_main | 1:83ace7df2c63 | 251 | } |
| JKsoft_main | 1:83ace7df2c63 | 252 | |
| JKsoft_main | 1:83ace7df2c63 | 253 | |
| JKsoft_main | 1:83ace7df2c63 | 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) |
| JKsoft_main | 1:83ace7df2c63 | 255 | /** |
| JKsoft_main | 1:83ace7df2c63 | 256 | * \brief Find peaks |
| JKsoft_main | 1:83ace7df2c63 | 257 | * \par Details |
| JKsoft_main | 1:83ace7df2c63 | 258 | * Find at most MAX_NUM peaks above MIN_HEIGHT separated by at least MIN_DISTANCE |
| JKsoft_main | 1:83ace7df2c63 | 259 | * |
| JKsoft_main | 1:83ace7df2c63 | 260 | * \retval None |
| JKsoft_main | 1:83ace7df2c63 | 261 | */ |
| JKsoft_main | 1:83ace7df2c63 | 262 | { |
| JKsoft_main | 1:83ace7df2c63 | 263 | maxim_peaks_above_min_height( pn_locs, pn_npks, pn_x, n_size, n_min_height ); |
| JKsoft_main | 1:83ace7df2c63 | 264 | maxim_remove_close_peaks( pn_locs, pn_npks, pn_x, n_min_distance ); |
| JKsoft_main | 1:83ace7df2c63 | 265 | *pn_npks = min( *pn_npks, n_max_num ); |
| JKsoft_main | 1:83ace7df2c63 | 266 | } |
| JKsoft_main | 1:83ace7df2c63 | 267 | |
| JKsoft_main | 1:83ace7df2c63 | 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) |
| JKsoft_main | 1:83ace7df2c63 | 269 | /** |
| JKsoft_main | 1:83ace7df2c63 | 270 | * \brief Find peaks above n_min_height |
| JKsoft_main | 1:83ace7df2c63 | 271 | * \par Details |
| JKsoft_main | 1:83ace7df2c63 | 272 | * Find all peaks above MIN_HEIGHT |
| JKsoft_main | 1:83ace7df2c63 | 273 | * |
| JKsoft_main | 1:83ace7df2c63 | 274 | * \retval None |
| JKsoft_main | 1:83ace7df2c63 | 275 | */ |
| JKsoft_main | 1:83ace7df2c63 | 276 | { |
| JKsoft_main | 1:83ace7df2c63 | 277 | int32_t i = 1, n_width; |
| JKsoft_main | 1:83ace7df2c63 | 278 | *pn_npks = 0; |
| JKsoft_main | 1:83ace7df2c63 | 279 | |
| JKsoft_main | 1:83ace7df2c63 | 280 | while (i < n_size-1){ |
| JKsoft_main | 1:83ace7df2c63 | 281 | if (pn_x[i] > n_min_height && pn_x[i] > pn_x[i-1]){ // find left edge of potential peaks |
| JKsoft_main | 1:83ace7df2c63 | 282 | n_width = 1; |
| JKsoft_main | 1:83ace7df2c63 | 283 | while (i+n_width < n_size && pn_x[i] == pn_x[i+n_width]) // find flat peaks |
| JKsoft_main | 1:83ace7df2c63 | 284 | n_width++; |
| JKsoft_main | 1:83ace7df2c63 | 285 | if (pn_x[i] > pn_x[i+n_width] && (*pn_npks) < 15 ){ // find right edge of peaks |
| JKsoft_main | 1:83ace7df2c63 | 286 | pn_locs[(*pn_npks)++] = i; |
| JKsoft_main | 1:83ace7df2c63 | 287 | // for flat peaks, peak location is left edge |
| JKsoft_main | 1:83ace7df2c63 | 288 | i += n_width+1; |
| JKsoft_main | 1:83ace7df2c63 | 289 | } |
| JKsoft_main | 1:83ace7df2c63 | 290 | else |
| JKsoft_main | 1:83ace7df2c63 | 291 | i += n_width; |
| JKsoft_main | 1:83ace7df2c63 | 292 | } |
| JKsoft_main | 1:83ace7df2c63 | 293 | else |
| JKsoft_main | 1:83ace7df2c63 | 294 | i++; |
| JKsoft_main | 1:83ace7df2c63 | 295 | } |
| JKsoft_main | 1:83ace7df2c63 | 296 | } |
| JKsoft_main | 1:83ace7df2c63 | 297 | |
| JKsoft_main | 1:83ace7df2c63 | 298 | |
| JKsoft_main | 1:83ace7df2c63 | 299 | void maxim_remove_close_peaks(int32_t *pn_locs, int32_t *pn_npks, int32_t *pn_x,int32_t n_min_distance) |
| JKsoft_main | 1:83ace7df2c63 | 300 | /** |
| JKsoft_main | 1:83ace7df2c63 | 301 | * \brief Remove peaks |
| JKsoft_main | 1:83ace7df2c63 | 302 | * \par Details |
| JKsoft_main | 1:83ace7df2c63 | 303 | * Remove peaks separated by less than MIN_DISTANCE |
| JKsoft_main | 1:83ace7df2c63 | 304 | * |
| JKsoft_main | 1:83ace7df2c63 | 305 | * \retval None |
| JKsoft_main | 1:83ace7df2c63 | 306 | */ |
| JKsoft_main | 1:83ace7df2c63 | 307 | { |
| JKsoft_main | 1:83ace7df2c63 | 308 | |
| JKsoft_main | 1:83ace7df2c63 | 309 | int32_t i, j, n_old_npks, n_dist; |
| JKsoft_main | 1:83ace7df2c63 | 310 | |
| JKsoft_main | 1:83ace7df2c63 | 311 | /* Order peaks from large to small */ |
| JKsoft_main | 1:83ace7df2c63 | 312 | maxim_sort_indices_descend( pn_x, pn_locs, *pn_npks ); |
| JKsoft_main | 1:83ace7df2c63 | 313 | |
| JKsoft_main | 1:83ace7df2c63 | 314 | for ( i = -1; i < *pn_npks; i++ ){ |
| JKsoft_main | 1:83ace7df2c63 | 315 | n_old_npks = *pn_npks; |
| JKsoft_main | 1:83ace7df2c63 | 316 | *pn_npks = i+1; |
| JKsoft_main | 1:83ace7df2c63 | 317 | for ( j = i+1; j < n_old_npks; j++ ){ |
| JKsoft_main | 1:83ace7df2c63 | 318 | n_dist = pn_locs[j] - ( i == -1 ? -1 : pn_locs[i] ); // lag-zero peak of autocorr is at index -1 |
| JKsoft_main | 1:83ace7df2c63 | 319 | if ( n_dist > n_min_distance || n_dist < -n_min_distance ) |
| JKsoft_main | 1:83ace7df2c63 | 320 | pn_locs[(*pn_npks)++] = pn_locs[j]; |
| JKsoft_main | 1:83ace7df2c63 | 321 | } |
| JKsoft_main | 1:83ace7df2c63 | 322 | } |
| JKsoft_main | 1:83ace7df2c63 | 323 | |
| JKsoft_main | 1:83ace7df2c63 | 324 | // Resort indices longo ascending order |
| JKsoft_main | 1:83ace7df2c63 | 325 | maxim_sort_ascend( pn_locs, *pn_npks ); |
| JKsoft_main | 1:83ace7df2c63 | 326 | } |
| JKsoft_main | 1:83ace7df2c63 | 327 | |
| JKsoft_main | 1:83ace7df2c63 | 328 | void maxim_sort_ascend(int32_t *pn_x,int32_t n_size) |
| JKsoft_main | 1:83ace7df2c63 | 329 | /** |
| JKsoft_main | 1:83ace7df2c63 | 330 | * \brief Sort array |
| JKsoft_main | 1:83ace7df2c63 | 331 | * \par Details |
| JKsoft_main | 1:83ace7df2c63 | 332 | * Sort array in ascending order (insertion sort algorithm) |
| JKsoft_main | 1:83ace7df2c63 | 333 | * |
| JKsoft_main | 1:83ace7df2c63 | 334 | * \retval None |
| JKsoft_main | 1:83ace7df2c63 | 335 | */ |
| JKsoft_main | 1:83ace7df2c63 | 336 | { |
| JKsoft_main | 1:83ace7df2c63 | 337 | int32_t i, j, n_temp; |
| JKsoft_main | 1:83ace7df2c63 | 338 | for (i = 1; i < n_size; i++) { |
| JKsoft_main | 1:83ace7df2c63 | 339 | n_temp = pn_x[i]; |
| JKsoft_main | 1:83ace7df2c63 | 340 | for (j = i; j > 0 && n_temp < pn_x[j-1]; j--) |
| JKsoft_main | 1:83ace7df2c63 | 341 | pn_x[j] = pn_x[j-1]; |
| JKsoft_main | 1:83ace7df2c63 | 342 | pn_x[j] = n_temp; |
| JKsoft_main | 1:83ace7df2c63 | 343 | } |
| JKsoft_main | 1:83ace7df2c63 | 344 | } |
| JKsoft_main | 1:83ace7df2c63 | 345 | |
| JKsoft_main | 1:83ace7df2c63 | 346 | void maxim_sort_indices_descend(int32_t *pn_x, int32_t *pn_indx, int32_t n_size) |
| JKsoft_main | 1:83ace7df2c63 | 347 | /** |
| JKsoft_main | 1:83ace7df2c63 | 348 | * \brief Sort indices |
| JKsoft_main | 1:83ace7df2c63 | 349 | * \par Details |
| JKsoft_main | 1:83ace7df2c63 | 350 | * Sort indices according to descending order (insertion sort algorithm) |
| JKsoft_main | 1:83ace7df2c63 | 351 | * |
| JKsoft_main | 1:83ace7df2c63 | 352 | * \retval None |
| JKsoft_main | 1:83ace7df2c63 | 353 | */ |
| JKsoft_main | 1:83ace7df2c63 | 354 | { |
| JKsoft_main | 1:83ace7df2c63 | 355 | int32_t i, j, n_temp; |
| JKsoft_main | 1:83ace7df2c63 | 356 | for (i = 1; i < n_size; i++) { |
| JKsoft_main | 1:83ace7df2c63 | 357 | n_temp = pn_indx[i]; |
| JKsoft_main | 1:83ace7df2c63 | 358 | for (j = i; j > 0 && pn_x[n_temp] > pn_x[pn_indx[j-1]]; j--) |
| JKsoft_main | 1:83ace7df2c63 | 359 | pn_indx[j] = pn_indx[j-1]; |
| JKsoft_main | 1:83ace7df2c63 | 360 | pn_indx[j] = n_temp; |
| JKsoft_main | 1:83ace7df2c63 | 361 | } |
| JKsoft_main | 1:83ace7df2c63 | 362 | } |
| JKsoft_main | 1:83ace7df2c63 | 363 |