pico is recognized
Dependencies: max32625pico mbed SerialInterface USBDevice
Diff: algorithm/algorithm.cpp
- Revision:
- 3:7c0fb55eb3ff
- Parent:
- 2:560e76e77544
- Child:
- 4:5273ab1085ab
--- a/algorithm/algorithm.cpp Thu Apr 21 18:25:34 2016 +0000 +++ b/algorithm/algorithm.cpp Thu Apr 21 19:38:17 2016 +0000 @@ -62,8 +62,8 @@ #include "algorithm.h" #include "mbed.h" -void maxim_heart_rate_and_oxygen_saturation(uint32_t *un_ir_buffer , int32_t n_ir_buffer_length, uint32_t *un_red_buffer , int32_t *n_spo2, int8_t *ch_spo2_valid , - int32_t *n_heart_rate , int8_t *ch_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 @@ -71,13 +71,13 @@ * Since this algorithm is aiming for Arm M0/M3. formaula for SPO2 did not achieve the accuracy due to register overflow. * Thus, accurate SPO2 is precalculated and save longo uch_spo2_table[] per each ratio. * -* \param[in] *un_ir_buffer - IR sensor data buffer +* \param[in] *pun_ir_buffer - IR sensor data buffer * \param[in] n_ir_buffer_length - IR sensor data buffer length -* \param[in] *un_red_buffer - Red sensor data buffer -* \param[out] *n_spo2 - Calculated SpO2 value -* \param[out] *ch_spo2_valid - 1 if the calculated SpO2 value is valid -* \param[out] *n_heart_rate - Calculated heart rate value -* \param[out] *ch_hr_valid - 1 if the calculated heart rate value is valid +* \param[in] *pun_red_buffer - Red sensor data buffer +* \param[out] *pn_spo2 - Calculated SpO2 value +* \param[out] *pch_spo2_valid - 1 if the calculated SpO2 value is valid +* \param[out] *pn_heart_rate - Calculated heart rate value +* \param[out] *pch_hr_valid - 1 if the calculated heart rate value is valid * * \retval None */ @@ -88,37 +88,37 @@ 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 n_ir_valley_locs[15] ; - int32_t n_exact_ir_valley_locs[15] ; - int32_t n_dx_peak_locs[15] ; + 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 n_ratio[5],n_ratio_average; + 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 += un_ir_buffer[k] ; + 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++ ) n_x[k] = un_ir_buffer[k] - un_ir_mean ; + 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= ( n_x[k]+n_x[k+1]+ n_x[k+2]+ n_x[k+3]); - n_x[k]= n_denom/(int32_t)4; + 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++) - n_dx[k]= (n_x[k+1]- n_x[k]); + an_dx[k]= (an_x[k+1]- an_x[k]); - // 2-pt Moving Average to n_dx + // 2-pt Moving Average to an_dx for(k=0; k< BUFFER_SIZE-MA4_SIZE-2; k++){ - n_dx[k] = ( n_dx[k]+n_dx[k+1])/2 ; + an_dx[k] = ( an_dx[k]+an_dx[k+1])/2 ; } // hamming window @@ -126,86 +126,86 @@ for ( i=0 ; i<BUFFER_SIZE-HAMMING_SIZE-MA4_SIZE-2 ;i++){ s= 0; for( k=i; k<i+ HAMMING_SIZE ;k++){ - s -= n_dx[k] *uw_hamm[k-i] ; + s -= an_dx[k] *auw_hamm[k-i] ; } - n_dx[i]= s/ (int32_t)1146; // divide by sum of uw_hamm + an_dx[i]= s/ (int32_t)1146; // divide by sum of auw_hamm } n_th1=0; // threshold calculation for ( k=0 ; k<BUFFER_SIZE-HAMMING_SIZE ;k++){ - n_th1 += ((n_dx[k]>0)? n_dx[k] : ((int32_t)0-n_dx[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( n_dx_peak_locs, &n_npks, n_dx, BUFFER_SIZE-HAMMING_SIZE, n_th1, 8, 5 );//peak_height, peak_distance, max_num_peaks + 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 += (n_dx_peak_locs[k] -n_dx_peak_locs[k -1] ) ; + 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); - *n_heart_rate =(int32_t)( 6000/ n_peak_interval_sum );// beats per minutes - //prlongf(">>> *n_heart_rate= %d \n", *n_heart_rate) ; - *ch_hr_valid = 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 { - *n_heart_rate = -999; - *ch_hr_valid = 0; + *pn_heart_rate = -999; + *pch_hr_valid = 0; } for ( k=0 ; k<n_npks ;k++) - n_ir_valley_locs[k]= n_dx_peak_locs[k] +HAMMING_SIZE /2; + 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++ ) { - n_x[k] = un_ir_buffer[k] ; - n_y[k] = un_red_buffer[k] ; + an_x[k] = pun_ir_buffer[k] ; + an_y[k] = pun_red_buffer[k] ; } - // find precise min near n_ir_valley_locs + // 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=n_ir_valley_locs[k]; + 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 (n_x[i]<n_c_min){ + if (an_x[i]<n_c_min){ if (un_only_once >0){ un_only_once =0; } - n_c_min= n_x[i] ; - n_exact_ir_valley_locs[k]=i; + 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 ){ - *n_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range - *ch_spo2_valid = 0; + *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++){ - n_x[k]=( n_x[k]+n_x[k+1]+ n_x[k+2]+ n_x[k+3])/(int32_t)4; - n_y[k]=( n_y[k]+n_y[k+1]+ n_y[k+2]+ n_y[k+3])/(int32_t)4; + 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; } - //using n_exact_ir_valley_locs , find ir-red DC andir-red AC for SPO2 calibration ratio + //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++) n_ratio[k]=0; + for(k=0; k< 5; k++) an_ratio[k]=0; for (k=0; k< n_exact_ir_valley_locs_count; k++){ - if (n_exact_ir_valley_locs[k] > BUFFER_SIZE ){ - *n_spo2 = -999 ; // do not use SPO2 since valley loc is out of range - *ch_spo2_valid = 0; + 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; } } @@ -215,58 +215,58 @@ 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 ", n_exact_ir_valley_locs[k], n_exact_ir_valley_locs[k+1]); - if (n_exact_ir_valley_locs[k+1]-n_exact_ir_valley_locs[k] >10){ - for (i=n_exact_ir_valley_locs[k]; i< n_exact_ir_valley_locs[k+1]; i++){ + // 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 (n_x[i]> n_x_dc_max) {n_x_dc_max =n_x[i];n_x_dc_max_idx =i; } - if (n_y[i]> n_y_dc_max) {n_y_dc_max =n_y[i];n_y_dc_max_idx=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= (n_y[n_exact_ir_valley_locs[k+1]] - n_y[n_exact_ir_valley_locs[k] ] )*(n_y_dc_max_idx -n_exact_ir_valley_locs[k]); //red - n_y_ac= n_y[n_exact_ir_valley_locs[k]] + n_y_ac/ (n_exact_ir_valley_locs[k+1] - n_exact_ir_valley_locs[k]) ; + 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= n_y[n_y_dc_max_idx] - n_y_ac; // subracting linear DC compoenents from raw - n_x_ac= (n_x[n_exact_ir_valley_locs[k+1]] - n_x[n_exact_ir_valley_locs[k] ] )*(n_x_dc_max_idx -n_exact_ir_valley_locs[k]); // ir - n_x_ac= n_x[n_exact_ir_valley_locs[k]] + n_x_ac/ (n_exact_ir_valley_locs[k+1] - n_exact_ir_valley_locs[k]); - n_x_ac= n_x[n_y_dc_max_idx] - n_x_ac; // subracting linear DC compoenents from raw + 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) { - n_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) ; + 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("n_ratio[%d]= %d n_exact_ir_valley_locs[k] =%d , n_exact_ir_valley_locs[%d] =%d \n",k, n_ratio[k] ,n_exact_ir_valley_locs[k] ,k+1, n_exact_ir_valley_locs[k+1] ) ; + // 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(n_ratio, n_i_ratio_count); + 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 =( n_ratio[n_middle_idx-1] +n_ratio[n_middle_idx])/2; // use median + n_ratio_average =( an_ratio[n_middle_idx-1] +an_ratio[n_middle_idx])/2; // use median else - n_ratio_average = n_ratio[n_middle_idx ]; + 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] ; - *n_spo2 = n_spo2_calc ; - *ch_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 + *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{ - *n_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range - *ch_spo2_valid = 0; + *pn_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range + *pch_spo2_valid = 0; } } -void maxim_find_peaks( int32_t *n_locs, int32_t *n_npks, int32_t *n_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 @@ -275,12 +275,12 @@ * \retval None */ { - maxim_peaks_above_min_height( n_locs, n_npks, n_x, n_size, n_min_height ); - maxim_remove_close_peaks( n_locs, n_npks, n_x, n_min_distance ); - *n_npks = min( *n_npks, n_max_num ); + maxim_peaks_above_min_height( pn_locs, pn_npks, pn_x, n_size, n_min_height ); + maxim_remove_close_peaks( pn_locs, pn_npks, pn_x, n_min_distance ); + *pn_npks = min( *pn_npks, n_max_num ); } -void maxim_peaks_above_min_height( int32_t *n_locs, int32_t *n_npks, int32_t *n_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 @@ -290,15 +290,15 @@ */ { int32_t i = 1, n_width; - *n_npks = 0; + *pn_npks = 0; while (i < n_size-1){ - if (n_x[i] > n_min_height && n_x[i] > n_x[i-1]){ // find left edge of potential peaks + if (pn_x[i] > n_min_height && pn_x[i] > pn_x[i-1]){ // find left edge of potential peaks n_width = 1; - while (i+n_width < n_size && n_x[i] == n_x[i+n_width]) // find flat peaks + while (i+n_width < n_size && pn_x[i] == pn_x[i+n_width]) // find flat peaks n_width++; - if (n_x[i] > n_x[i+n_width] && (*n_npks) < 15 ){ // find right edge of peaks - n_locs[(*n_npks)++] = i; + 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 i += n_width+1; } @@ -311,7 +311,7 @@ } -void maxim_remove_close_peaks( int32_t *n_locs, int32_t *n_npks, int32_t *n_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 @@ -324,23 +324,23 @@ int32_t i, j, n_old_npks, n_dist; /* Order peaks from large to small */ - maxim_sort_indices_descend( n_x, n_locs, *n_npks ); + maxim_sort_indices_descend( pn_x, pn_locs, *pn_npks ); - for ( i = -1; i < *n_npks; i++ ){ - n_old_npks = *n_npks; - *n_npks = i+1; + for ( i = -1; i < *pn_npks; i++ ){ + n_old_npks = *pn_npks; + *pn_npks = i+1; for ( j = i+1; j < n_old_npks; j++ ){ - n_dist = n_locs[j] - ( i == -1 ? -1 : n_locs[i] ); // lag-zero peak of autocorr is at index -1 + n_dist = pn_locs[j] - ( i == -1 ? -1 : pn_locs[i] ); // lag-zero peak of autocorr is at index -1 if ( n_dist > n_min_distance || n_dist < -n_min_distance ) - n_locs[(*n_npks)++] = n_locs[j]; + pn_locs[(*pn_npks)++] = pn_locs[j]; } } // Resort indices longo ascending order - maxim_sort_ascend( n_locs, *n_npks ); + maxim_sort_ascend( pn_locs, *pn_npks ); } -void maxim_sort_ascend(int32_t *n_x, int32_t n_size) +void maxim_sort_ascend(int32_t *pn_x, int32_t n_size) /** * \brief Sort array * \par Details @@ -351,14 +351,14 @@ { int32_t i, j, n_temp; for (i = 1; i < n_size; i++) { - n_temp = n_x[i]; - for (j = i; j > 0 && n_temp < n_x[j-1]; j--) - n_x[j] = n_x[j-1]; - n_x[j] = n_temp; + n_temp = pn_x[i]; + for (j = i; j > 0 && n_temp < pn_x[j-1]; j--) + pn_x[j] = pn_x[j-1]; + pn_x[j] = n_temp; } } -void maxim_sort_indices_descend( int32_t *n_x, int32_t *n_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 @@ -369,10 +369,10 @@ { int32_t i, j, n_temp; for (i = 1; i < n_size; i++) { - n_temp = n_indx[i]; - for (j = i; j > 0 && n_x[n_temp] > n_x[n_indx[j-1]]; j--) - n_indx[j] = n_indx[j-1]; - n_indx[j] = n_temp; + n_temp = pn_indx[i]; + for (j = i; j > 0 && pn_x[n_temp] > pn_x[pn_indx[j-1]]; j--) + pn_indx[j] = pn_indx[j-1]; + pn_indx[j] = n_temp; } }