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Changes added for the DISCO-L476VG
Diff: algorithm/algorithm.cpp
- Revision:
- 4:5273ab1085ab
- Parent:
- 3:7c0fb55eb3ff
diff -r 7c0fb55eb3ff -r 5273ab1085ab algorithm/algorithm.cpp --- a/algorithm/algorithm.cpp Thu Apr 21 19:38:17 2016 +0000 +++ b/algorithm/algorithm.cpp Thu May 19 22:04:06 2016 +0000 @@ -4,31 +4,28 @@ * Filename: algorithm.cpp * Description: This module calculates the heart rate/SpO2 level * -* Revision History: -*\n 1-18-2016 Rev 01.00 SK Initial release. -*\n * * -------------------------------------------------------------------- * * This code follows the following naming conventions: * -*\n char ch_pmod_value -*\n char (array) s_pmod_s_string[16] -*\n float f_pmod_value -*\n int32_t n_pmod_value -*\n int32_t (array) an_pmod_value[16] -*\n int16_t w_pmod_value -*\n int16_t (array) aw_pmod_value[16] -*\n uint16_t uw_pmod_value -*\n uint16_t (array) auw_pmod_value[16] -*\n uint8_t uch_pmod_value -*\n uint8_t (array) auch_pmod_buffer[16] -*\n uint32_t un_pmod_value -*\n int32_t * pn_pmod_value +* char ch_pmod_value +* char (array) s_pmod_s_string[16] +* float f_pmod_value +* int32_t n_pmod_value +* int32_t (array) an_pmod_value[16] +* int16_t w_pmod_value +* int16_t (array) aw_pmod_value[16] +* uint16_t uw_pmod_value +* uint16_t (array) auw_pmod_value[16] +* uint8_t uch_pmod_value +* uint8_t (array) auch_pmod_buffer[16] +* uint32_t un_pmod_value +* int32_t * pn_pmod_value * * ------------------------------------------------------------------------- */ /******************************************************************************* -* Copyright (C) 2015 Maxim Integrated Products, Inc., All Rights Reserved. +* Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), @@ -62,8 +59,8 @@ #include "algorithm.h" #include "mbed.h" -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 , - int32_t *pn_heart_rate , int8_t *pch_hr_valid) +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, + int32_t *pn_heart_rate, int8_t *pch_hr_valid) /** * \brief Calculate the heart rate and SpO2 level * \par Details @@ -82,191 +79,179 @@ * \retval None */ { - + uint32_t un_ir_mean ,un_only_once ; + int32_t k ,n_i_ratio_count; + int32_t i,s ,m, n_exact_ir_valley_locs_count ,n_middle_idx; + int32_t n_th1, n_npks,n_c_min; + int32_t an_ir_valley_locs[15] ; + int32_t an_exact_ir_valley_locs[15] ; + int32_t an_dx_peak_locs[15] ; + int32_t n_peak_interval_sum; + + int32_t n_y_ac, n_x_ac; + int32_t n_spo2_calc; + int32_t n_y_dc_max, n_x_dc_max; + int32_t n_y_dc_max_idx, n_x_dc_max_idx; + int32_t an_ratio[5],n_ratio_average; + int32_t n_nume, n_denom ; + // remove DC of ir signal + un_ir_mean =0; + for (k=0 ; k<n_ir_buffer_length ; k++ ) un_ir_mean += pun_ir_buffer[k] ; + un_ir_mean =un_ir_mean/n_ir_buffer_length ; + for (k=0 ; k<n_ir_buffer_length ; k++ ) an_x[k] = pun_ir_buffer[k] - un_ir_mean ; + + // 4 pt Moving Average + for(k=0; k< BUFFER_SIZE-MA4_SIZE; k++){ + n_denom= ( an_x[k]+an_x[k+1]+ an_x[k+2]+ an_x[k+3]); + an_x[k]= n_denom/(int32_t)4; + } - uint32_t un_ir_mean ,un_only_once ; - int32_t k ,n_i_ratio_count; - int32_t i,s ,m, n_exact_ir_valley_locs_count ,n_middle_idx; - int32_t n_th1, n_npks,n_c_min; - int32_t an_ir_valley_locs[15] ; - int32_t an_exact_ir_valley_locs[15] ; - int32_t an_dx_peak_locs[15] ; - int32_t n_peak_interval_sum; - - int32_t n_y_ac, n_x_ac; - int32_t n_spo2_calc; - int32_t n_y_dc_max, n_x_dc_max; - int32_t n_y_dc_max_idx, n_x_dc_max_idx; - int32_t an_ratio[5],n_ratio_average; - int32_t n_nume, n_denom ; - // remove DC of ir signal - un_ir_mean =0; - for (k=0 ; k<n_ir_buffer_length ; k++ ) un_ir_mean += pun_ir_buffer[k] ; - un_ir_mean =un_ir_mean/n_ir_buffer_length ; - for (k=0 ; k<n_ir_buffer_length ; k++ ) an_x[k] = pun_ir_buffer[k] - un_ir_mean ; - - // 4 pt Moving Average - for(k=0; k< BUFFER_SIZE-MA4_SIZE; k++){ - n_denom= ( an_x[k]+an_x[k+1]+ an_x[k+2]+ an_x[k+3]); - an_x[k]= n_denom/(int32_t)4; - } - - // get difference of smoothed IR signal - - for( k=0; k<BUFFER_SIZE-MA4_SIZE-1; k++) - an_dx[k]= (an_x[k+1]- an_x[k]); + // get difference of smoothed IR signal + + for( k=0; k<BUFFER_SIZE-MA4_SIZE-1; k++) + an_dx[k]= (an_x[k+1]- an_x[k]); - // 2-pt Moving Average to an_dx - for(k=0; k< BUFFER_SIZE-MA4_SIZE-2; k++){ - an_dx[k] = ( an_dx[k]+an_dx[k+1])/2 ; - } - - // hamming window - // flip wave form so that we can detect valley with peak detector - for ( i=0 ; i<BUFFER_SIZE-HAMMING_SIZE-MA4_SIZE-2 ;i++){ - s= 0; - for( k=i; k<i+ HAMMING_SIZE ;k++){ - s -= an_dx[k] *auw_hamm[k-i] ; - } - an_dx[i]= s/ (int32_t)1146; // divide by sum of auw_hamm - } + // 2-pt Moving Average to an_dx + for(k=0; k< BUFFER_SIZE-MA4_SIZE-2; k++){ + an_dx[k] = ( an_dx[k]+an_dx[k+1])/2 ; + } - - n_th1=0; // threshold calculation - for ( k=0 ; k<BUFFER_SIZE-HAMMING_SIZE ;k++){ - n_th1 += ((an_dx[k]>0)? an_dx[k] : ((int32_t)0-an_dx[k])) ; - } - n_th1= n_th1/ ( BUFFER_SIZE-HAMMING_SIZE); - // peak location is acutally index for sharpest location of raw signal since we flipped the signal - 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 + // hamming window + // flip wave form so that we can detect valley with peak detector + for ( i=0 ; i<BUFFER_SIZE-HAMMING_SIZE-MA4_SIZE-2 ;i++){ + s= 0; + for( k=i; k<i+ HAMMING_SIZE ;k++){ + s -= an_dx[k] *auw_hamm[k-i] ; + } + an_dx[i]= s/ (int32_t)1146; // divide by sum of auw_hamm + } - n_peak_interval_sum =0; - if (n_npks>=2){ - for (k=1; k<n_npks; k++) - n_peak_interval_sum += (an_dx_peak_locs[k] -an_dx_peak_locs[k -1] ) ; - n_peak_interval_sum =n_peak_interval_sum/(n_npks-1); - *pn_heart_rate =(int32_t)( 6000/ n_peak_interval_sum );// beats per minutes - //prlongf(">>> *pn_heart_rate= %d \n", *pn_heart_rate) ; - *pch_hr_valid = 1; - } - else { - *pn_heart_rate = -999; - *pch_hr_valid = 0; - } - - for ( k=0 ; k<n_npks ;k++) - an_ir_valley_locs[k]= an_dx_peak_locs[k] +HAMMING_SIZE /2; + + n_th1=0; // threshold calculation + for ( k=0 ; k<BUFFER_SIZE-HAMMING_SIZE ;k++){ + n_th1 += ((an_dx[k]>0)? an_dx[k] : ((int32_t)0-an_dx[k])) ; + } + n_th1= n_th1/ ( BUFFER_SIZE-HAMMING_SIZE); + // peak location is acutally index for sharpest location of raw signal since we flipped the signal + 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 + + n_peak_interval_sum =0; + if (n_npks>=2){ + for (k=1; k<n_npks; k++) + n_peak_interval_sum += (an_dx_peak_locs[k]-an_dx_peak_locs[k -1]); + n_peak_interval_sum=n_peak_interval_sum/(n_npks-1); + *pn_heart_rate=(int32_t)(6000/n_peak_interval_sum);// beats per minutes + *pch_hr_valid = 1; + } + else { + *pn_heart_rate = -999; + *pch_hr_valid = 0; + } + + for ( k=0 ; k<n_npks ;k++) + an_ir_valley_locs[k]=an_dx_peak_locs[k]+HAMMING_SIZE/2; - // raw value : RED(=y) and IR(=X) - // we need to assess DC and AC value of ir and red PPG. - for (k=0 ; k<n_ir_buffer_length ; k++ ) { - an_x[k] = pun_ir_buffer[k] ; - an_y[k] = pun_red_buffer[k] ; - } + // raw value : RED(=y) and IR(=X) + // we need to assess DC and AC value of ir and red PPG. + for (k=0 ; k<n_ir_buffer_length ; k++ ) { + an_x[k] = pun_ir_buffer[k] ; + an_y[k] = pun_red_buffer[k] ; + } + + // find precise min near an_ir_valley_locs + n_exact_ir_valley_locs_count =0; + for(k=0 ; k<n_npks ;k++){ + un_only_once =1; + m=an_ir_valley_locs[k]; + n_c_min= 16777216;//2^24; + if (m+5 < BUFFER_SIZE-HAMMING_SIZE && m-5 >0){ + for(i= m-5;i<m+5; i++) + if (an_x[i]<n_c_min){ + if (un_only_once >0){ + un_only_once =0; + } + n_c_min= an_x[i] ; + an_exact_ir_valley_locs[k]=i; + } + if (un_only_once ==0) + n_exact_ir_valley_locs_count ++ ; + } + } + if (n_exact_ir_valley_locs_count <2 ){ + *pn_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range + *pch_spo2_valid = 0; + return; + } + // 4 pt MA + for(k=0; k< BUFFER_SIZE-MA4_SIZE; k++){ + an_x[k]=( an_x[k]+an_x[k+1]+ an_x[k+2]+ an_x[k+3])/(int32_t)4; + an_y[k]=( an_y[k]+an_y[k+1]+ an_y[k+2]+ an_y[k+3])/(int32_t)4; + } - // find precise min near an_ir_valley_locs - n_exact_ir_valley_locs_count =0; - for ( k=0 ; k<n_npks ;k++){ - un_only_once =1; - m=an_ir_valley_locs[k]; - n_c_min= 16777216;//2^24; - if (m+5 < BUFFER_SIZE-HAMMING_SIZE && m-5 >0){ - - for(i= m-5;i<m+5; i++) - if (an_x[i]<n_c_min){ - if (un_only_once >0){ - un_only_once =0; - } - n_c_min= an_x[i] ; - an_exact_ir_valley_locs[k]=i; - } - if (un_only_once ==0) n_exact_ir_valley_locs_count ++ ; + //using an_exact_ir_valley_locs , find ir-red DC andir-red AC for SPO2 calibration ratio + //finding AC/DC maximum of raw ir * red between two valley locations + n_ratio_average =0; + n_i_ratio_count =0; + + for(k=0; k< 5; k++) an_ratio[k]=0; + for (k=0; k< n_exact_ir_valley_locs_count; k++){ + if (an_exact_ir_valley_locs[k] > BUFFER_SIZE ){ + *pn_spo2 = -999 ; // do not use SPO2 since valley loc is out of range + *pch_spo2_valid = 0; + return; + } + } + // find max between two valley locations + // and use ratio betwen AC compoent of Ir & Red and DC compoent of Ir & Red for SPO2 + + for (k=0; k< n_exact_ir_valley_locs_count-1; k++){ + n_y_dc_max= -16777216 ; + n_x_dc_max= - 16777216; + if (an_exact_ir_valley_locs[k+1]-an_exact_ir_valley_locs[k] >10){ + for (i=an_exact_ir_valley_locs[k]; i< an_exact_ir_valley_locs[k+1]; i++){ + if (an_x[i]> n_x_dc_max) {n_x_dc_max =an_x[i];n_x_dc_max_idx =i; } + if (an_y[i]> n_y_dc_max) {n_y_dc_max =an_y[i];n_y_dc_max_idx=i;} + } + 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 + 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]) ; + + + n_y_ac= an_y[n_y_dc_max_idx] - n_y_ac; // subracting linear DC compoenents from raw + 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 + 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]); + n_x_ac= an_x[n_y_dc_max_idx] - n_x_ac; // subracting linear DC compoenents from raw + n_nume=( n_y_ac *n_x_dc_max)>>7 ; //prepare X100 to preserve floating value + n_denom= ( n_x_ac *n_y_dc_max)>>7; + if (n_denom>0 && n_i_ratio_count <5 && n_nume != 0) + { + 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) ; + n_i_ratio_count++; } } - if (n_exact_ir_valley_locs_count <2 ){ - *pn_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range - *pch_spo2_valid = 0; - return; - } - // 4 pt MA - for(k=0; k< BUFFER_SIZE-MA4_SIZE; k++){ - an_x[k]=( an_x[k]+an_x[k+1]+ an_x[k+2]+ an_x[k+3])/(int32_t)4; - an_y[k]=( an_y[k]+an_y[k+1]+ an_y[k+2]+ an_y[k+3])/(int32_t)4; - - } + } + + maxim_sort_ascend(an_ratio, n_i_ratio_count); + n_middle_idx= n_i_ratio_count/2; + + if (n_middle_idx >1) + n_ratio_average =( an_ratio[n_middle_idx-1] +an_ratio[n_middle_idx])/2; // use median + else + n_ratio_average = an_ratio[n_middle_idx ]; - //using an_exact_ir_valley_locs , find ir-red DC andir-red AC for SPO2 calibration ratio - //finding AC/DC maximum of raw ir * red between two valley locations - n_ratio_average =0; - n_i_ratio_count = 0; - - for(k=0; k< 5; k++) an_ratio[k]=0; - for (k=0; k< n_exact_ir_valley_locs_count; k++){ - if (an_exact_ir_valley_locs[k] > BUFFER_SIZE ){ - *pn_spo2 = -999 ; // do not use SPO2 since valley loc is out of range - *pch_spo2_valid = 0; - return; - } - } - // find max between two valley locations - // and use ratio betwen AC compoent of Ir & Red and DC compoent of Ir & Red for SPO2 - - for (k=0; k< n_exact_ir_valley_locs_count-1; k++){ - n_y_dc_max= -16777216 ; - n_x_dc_max= - 16777216; - // printf("range=%d: %d\n ", an_exact_ir_valley_locs[k], an_exact_ir_valley_locs[k+1]); - if (an_exact_ir_valley_locs[k+1]-an_exact_ir_valley_locs[k] >10){ - for (i=an_exact_ir_valley_locs[k]; i< an_exact_ir_valley_locs[k+1]; i++){ - - if (an_x[i]> n_x_dc_max) {n_x_dc_max =an_x[i];n_x_dc_max_idx =i; } - if (an_y[i]> n_y_dc_max) {n_y_dc_max =an_y[i];n_y_dc_max_idx=i;} - } - 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 - 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]) ; - - - n_y_ac= an_y[n_y_dc_max_idx] - n_y_ac; // subracting linear DC compoenents from raw - 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 - 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]); - n_x_ac= an_x[n_y_dc_max_idx] - n_x_ac; // subracting linear DC compoenents from raw - n_nume=( n_y_ac *n_x_dc_max)>>7 ; //prepare X100 to preserve floating value - n_denom= ( n_x_ac *n_y_dc_max)>>7; - if (n_denom>0 && n_i_ratio_count <5 && n_nume != 0) - { - 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) ; - n_i_ratio_count++; - } - } - - // prlongf("an_ratio[%d]= %d an_exact_ir_valley_locs[k] =%d , an_exact_ir_valley_locs[%d] =%d \n",k, an_ratio[k] ,an_exact_ir_valley_locs[k] ,k+1, an_exact_ir_valley_locs[k+1] ) ; - // prlongf("n_nume= %d ,n_denom= %d n_y_ac = %d, n_x_dc_max = %d, n_x_ac= %d, n_y_dc_max = %d\n",n_nume, n_denom, n_y_ac ,n_x_dc_max ,n_x_ac ,n_y_dc_max ); - - } - - maxim_sort_ascend(an_ratio, n_i_ratio_count); - n_middle_idx= n_i_ratio_count/2; - - if (n_middle_idx >1) - n_ratio_average =( an_ratio[n_middle_idx-1] +an_ratio[n_middle_idx])/2; // use median - else - n_ratio_average = an_ratio[n_middle_idx ]; - - if( n_ratio_average>2 && n_ratio_average <184){ - n_spo2_calc= uch_spo2_table[n_ratio_average] ; - *pn_spo2 = n_spo2_calc ; - *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 - } - else{ - *pn_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range - *pch_spo2_valid = 0; - } - - + if( n_ratio_average>2 && n_ratio_average <184){ + n_spo2_calc= uch_spo2_table[n_ratio_average] ; + *pn_spo2 = n_spo2_calc ; + *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 + } + else{ + *pn_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range + *pch_spo2_valid = 0; + } } -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 ) +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) /** * \brief Find peaks * \par Details @@ -280,7 +265,7 @@ *pn_npks = min( *pn_npks, n_max_num ); } -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 ) +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) /** * \brief Find peaks above n_min_height * \par Details @@ -299,7 +284,7 @@ n_width++; if (pn_x[i] > pn_x[i+n_width] && (*pn_npks) < 15 ){ // find right edge of peaks pn_locs[(*pn_npks)++] = i; - // for flat peaks, peak location is left edge + // for flat peaks, peak location is left edge i += n_width+1; } else @@ -311,7 +296,7 @@ } -void maxim_remove_close_peaks( int32_t *pn_locs, int32_t *pn_npks, int32_t *pn_x, int32_t n_min_distance ) +void maxim_remove_close_peaks(int32_t *pn_locs, int32_t *pn_npks, int32_t *pn_x,int32_t n_min_distance) /** * \brief Remove peaks * \par Details @@ -340,7 +325,7 @@ maxim_sort_ascend( pn_locs, *pn_npks ); } -void maxim_sort_ascend(int32_t *pn_x, int32_t n_size) +void maxim_sort_ascend(int32_t *pn_x,int32_t n_size) /** * \brief Sort array * \par Details @@ -358,7 +343,7 @@ } } -void maxim_sort_indices_descend( int32_t *pn_x, int32_t *pn_indx, int32_t n_size) +void maxim_sort_indices_descend(int32_t *pn_x, int32_t *pn_indx, int32_t n_size) /** * \brief Sort indices * \par Details