MAXREFDES117_STM32 - Arduino version , update and tested on NUCLEO-L07…

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Christian Dupaty / Mbed 2 deprecated MAXREFDES117_STM32

Arduino version , update and tested on NUCLEO-L073RZ

Dependencies: mbed

Oximeter and pulse sensor, based on the Beer-Lambert gas absorption law

MAXREFDES117 ( MAX30102 ) from MAXIM, based on MAXIM library for Arduino

adaptation C.Dupaty 07-2017

Tested on STM32 NUCLEO-F411RE and NUCLEO-L073RZ

algorithm/algorithm.cpp@1:e88f22c6c1b0, 2016-04-20 (annotated)

Committer:: MaximGordon
Date:: Wed Apr 20 23:05:38 2016 +0000
Revision:: 1:e88f22c6c1b0
Parent:: 0:346a7fa07998
Child:: 2:560e76e77544

Who changed what in which revision?

User	Revision	Line number	New contents of line
MaximGordon	1:e88f22c6c1b0	1	/ \file algorithm.cpp ****************************************************
MaximGordon	0:346a7fa07998	2	*
MaximGordon	0:346a7fa07998	3	* Project: MAXREFDES117#
MaximGordon	1:e88f22c6c1b0	4	* Filename: algorithm.cpp
MaximGordon	0:346a7fa07998	5	* Description: This module calculates the heart rate/SpO2 level
MaximGordon	0:346a7fa07998	6	*
MaximGordon	0:346a7fa07998	7	* Revision History:
MaximGordon	0:346a7fa07998	8	*\n 1-18-2016 Rev 01.00 SK Initial release.
MaximGordon	0:346a7fa07998	9	*\n
MaximGordon	0:346a7fa07998	10	*
MaximGordon	0:346a7fa07998	11	* --------------------------------------------------------------------
MaximGordon	0:346a7fa07998	12	*
MaximGordon	0:346a7fa07998	13	* This code follows the following naming conventions:
MaximGordon	0:346a7fa07998	14	*
MaximGordon	0:346a7fa07998	15	*\n char ch_pmod_value
MaximGordon	0:346a7fa07998	16	*\n char (array) s_pmod_s_string[16]
MaximGordon	0:346a7fa07998	17	*\n float f_pmod_value
MaximGordon	0:346a7fa07998	18	*\n int32_t n_pmod_value
MaximGordon	0:346a7fa07998	19	*\n int32_t (array) an_pmod_value[16]
MaximGordon	0:346a7fa07998	20	*\n int16_t w_pmod_value
MaximGordon	0:346a7fa07998	21	*\n int16_t (array) aw_pmod_value[16]
MaximGordon	0:346a7fa07998	22	*\n uint16_t uw_pmod_value
MaximGordon	0:346a7fa07998	23	*\n uint16_t (array) auw_pmod_value[16]
MaximGordon	0:346a7fa07998	24	*\n uint8_t uch_pmod_value
MaximGordon	0:346a7fa07998	25	*\n uint8_t (array) auch_pmod_buffer[16]
MaximGordon	0:346a7fa07998	26	*\n uint32_t un_pmod_value
MaximGordon	0:346a7fa07998	27	\n int32_t pn_pmod_value
MaximGordon	0:346a7fa07998	28	*
MaximGordon	0:346a7fa07998	29	* ------------------------------------------------------------------------- */
MaximGordon	0:346a7fa07998	30	/*******************************************************************************
MaximGordon	0:346a7fa07998	31	* Copyright (C) 2015 Maxim Integrated Products, Inc., All Rights Reserved.
MaximGordon	0:346a7fa07998	32	*
MaximGordon	0:346a7fa07998	33	* Permission is hereby granted, free of charge, to any person obtaining a
MaximGordon	0:346a7fa07998	34	* copy of this software and associated documentation files (the "Software"),
MaximGordon	0:346a7fa07998	35	* to deal in the Software without restriction, including without limitation
MaximGordon	0:346a7fa07998	36	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
MaximGordon	0:346a7fa07998	37	* and/or sell copies of the Software, and to permit persons to whom the
MaximGordon	0:346a7fa07998	38	* Software is furnished to do so, subject to the following conditions:
MaximGordon	0:346a7fa07998	39	*
MaximGordon	0:346a7fa07998	40	* The above copyright notice and this permission notice shall be included
MaximGordon	0:346a7fa07998	41	* in all copies or substantial portions of the Software.
MaximGordon	0:346a7fa07998	42	*
MaximGordon	0:346a7fa07998	43	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
MaximGordon	0:346a7fa07998	44	* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MaximGordon	0:346a7fa07998	45	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
MaximGordon	0:346a7fa07998	46	* IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
MaximGordon	0:346a7fa07998	47	* OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
MaximGordon	0:346a7fa07998	48	* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
MaximGordon	0:346a7fa07998	49	* OTHER DEALINGS IN THE SOFTWARE.
MaximGordon	0:346a7fa07998	50	*
MaximGordon	0:346a7fa07998	51	* Except as contained in this notice, the name of Maxim Integrated
MaximGordon	0:346a7fa07998	52	* Products, Inc. shall not be used except as stated in the Maxim Integrated
MaximGordon	0:346a7fa07998	53	* Products, Inc. Branding Policy.
MaximGordon	0:346a7fa07998	54	*
MaximGordon	0:346a7fa07998	55	* The mere transfer of this software does not imply any licenses
MaximGordon	0:346a7fa07998	56	* of trade secrets, proprietary technology, copyrights, patents,
MaximGordon	0:346a7fa07998	57	* trademarks, maskwork rights, or any other form of intellectual
MaximGordon	0:346a7fa07998	58	* property whatsoever. Maxim Integrated Products, Inc. retains all
MaximGordon	0:346a7fa07998	59	* ownership rights.
MaximGordon	0:346a7fa07998	60	*******************************************************************************
MaximGordon	0:346a7fa07998	61	*/
MaximGordon	0:346a7fa07998	62	#include "algorithm.h"
MaximGordon	0:346a7fa07998	63	#include "mbed.h"
MaximGordon	0:346a7fa07998	64
MaximGordon	0:346a7fa07998	65	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 ,
MaximGordon	0:346a7fa07998	66	int32_t n_heart_rate , int8_t ch_hr_valid)
MaximGordon	0:346a7fa07998	67	/**
MaximGordon	0:346a7fa07998	68	* \brief Calculate the heart rate and SpO2 level
MaximGordon	0:346a7fa07998	69	* \par Details
MaximGordon	0:346a7fa07998	70	* By detecting peaks of PPG cycle and corresponding AC/DC of red/infra-red signal, the ratio for the SPO2 is computed.
MaximGordon	0:346a7fa07998	71	* Since this algorithm is aiming for Arm M0/M3. formaula for SPO2 did not achieve the accuracy due to register overflow.
MaximGordon	0:346a7fa07998	72	* Thus, accurate SPO2 is precalculated and save longo uch_spo2_table[] per each ratio.
MaximGordon	0:346a7fa07998	73	*
MaximGordon	0:346a7fa07998	74	* \param[in] *un_ir_buffer - IR sensor data buffer
MaximGordon	0:346a7fa07998	75	* \param[in] n_ir_buffer_length - IR sensor data buffer length
MaximGordon	0:346a7fa07998	76	* \param[in] *un_red_buffer - Red sensor data buffer
MaximGordon	0:346a7fa07998	77	* \param[out] *n_spo2 - Calculated SpO2 value
MaximGordon	0:346a7fa07998	78	* \param[out] *ch_spo2_valid - 1 if the calculated SpO2 value is valid
MaximGordon	0:346a7fa07998	79	* \param[out] *n_heart_rate - Calculated heart rate value
MaximGordon	0:346a7fa07998	80	* \param[out] *ch_hr_valid - 1 if the calculated heart rate value is valid
MaximGordon	0:346a7fa07998	81	*
MaximGordon	0:346a7fa07998	82	* \retval None
MaximGordon	0:346a7fa07998	83	*/
MaximGordon	0:346a7fa07998	84	{
MaximGordon	0:346a7fa07998	85
MaximGordon	0:346a7fa07998	86
MaximGordon	0:346a7fa07998	87	uint32_t irMean ,onlyOnce ;
MaximGordon	0:346a7fa07998	88	int32_t k ,iRatioCount;
MaximGordon	0:346a7fa07998	89	int32_t i,s ,m, exact_ir_valley_locs_count ,middleIdx;
MaximGordon	0:346a7fa07998	90	int32_t th1, n_npks,cMin;
MaximGordon	0:346a7fa07998	91	int32_t ir_valley_locs[15] ;
MaximGordon	0:346a7fa07998	92	int32_t exact_ir_valley_locs[15] ;
MaximGordon	0:346a7fa07998	93	int32_t dx_peak_locs[15] ;
MaximGordon	0:346a7fa07998	94	int32_t peakintervalSum;
MaximGordon	0:346a7fa07998	95
MaximGordon	0:346a7fa07998	96	int32_t yAC, xAC;
MaximGordon	0:346a7fa07998	97	int32_t spo2calc;
MaximGordon	0:346a7fa07998	98	int32_t yDCmax, xDCmax;
MaximGordon	0:346a7fa07998	99	int32_t yDCmaxIdx, xDCmaxIdx;
MaximGordon	0:346a7fa07998	100	int32_t ratio[5],ratioAverage;
MaximGordon	0:346a7fa07998	101	int32_t nume, denom ;
MaximGordon	0:346a7fa07998	102	// remove DC of ir signal
MaximGordon	0:346a7fa07998	103	irMean =0;
MaximGordon	0:346a7fa07998	104	for (k=0 ; k<n_ir_buffer_length ; k++ ) irMean += un_ir_buffer[k] ;
MaximGordon	0:346a7fa07998	105	irMean =irMean/n_ir_buffer_length ;
MaximGordon	0:346a7fa07998	106	for (k=0 ; k<n_ir_buffer_length ; k++ ) n_x[k] = un_ir_buffer[k] - irMean ;
MaximGordon	0:346a7fa07998	107
MaximGordon	0:346a7fa07998	108	// 4 pt Moving Average
MaximGordon	0:346a7fa07998	109	for(k=0; k< BUFFER_SIZE-MA4_SIZE; k++){
MaximGordon	0:346a7fa07998	110	denom= ( n_x[k]+n_x[k+1]+ n_x[k+2]+ n_x[k+3]);
MaximGordon	0:346a7fa07998	111	n_x[k]= denom/(int32_t)4;
MaximGordon	0:346a7fa07998	112	}
MaximGordon	0:346a7fa07998	113
MaximGordon	0:346a7fa07998	114	// get difference of smoothed IR signal
MaximGordon	0:346a7fa07998	115
MaximGordon	0:346a7fa07998	116	for( k=0; k<BUFFER_SIZE-MA4_SIZE-1; k++)
MaximGordon	0:346a7fa07998	117	n_dx[k]= (n_x[k+1]- n_x[k]);
MaximGordon	0:346a7fa07998	118
MaximGordon	0:346a7fa07998	119	// 2-pt Moving Average to n_dx
MaximGordon	0:346a7fa07998	120	for(k=0; k< BUFFER_SIZE-MA4_SIZE-2; k++){
MaximGordon	0:346a7fa07998	121	n_dx[k] = ( n_dx[k]+n_dx[k+1])/2 ;
MaximGordon	0:346a7fa07998	122	}
MaximGordon	0:346a7fa07998	123
MaximGordon	0:346a7fa07998	124	// hamming window
MaximGordon	0:346a7fa07998	125	// flip wave form so that we can detect valley with peak detector
MaximGordon	0:346a7fa07998	126	for ( i=0 ; i<BUFFER_SIZE-HAMMING_SIZE-MA4_SIZE-2 ;i++){
MaximGordon	0:346a7fa07998	127	s= 0;
MaximGordon	0:346a7fa07998	128	for( k=i; k<i+ HAMMING_SIZE ;k++){
MaximGordon	0:346a7fa07998	129	s -= n_dx[k] *uw_hamm[k-i] ;
MaximGordon	0:346a7fa07998	130	}
MaximGordon	0:346a7fa07998	131	n_dx[i]= s/ (int32_t)1146; // divide by sum of uw_hamm
MaximGordon	0:346a7fa07998	132	}
MaximGordon	0:346a7fa07998	133
MaximGordon	0:346a7fa07998	134
MaximGordon	0:346a7fa07998	135	th1=0; // threshold calculation
MaximGordon	0:346a7fa07998	136	for ( k=0 ; k<BUFFER_SIZE-HAMMING_SIZE ;k++){
MaximGordon	0:346a7fa07998	137	th1 += ((n_dx[k]>0)? n_dx[k] : ((int32_t)0-n_dx[k])) ;
MaximGordon	0:346a7fa07998	138	}
MaximGordon	0:346a7fa07998	139	th1= th1/ ( BUFFER_SIZE-HAMMING_SIZE);
MaximGordon	0:346a7fa07998	140	// peak location is acutally index for sharpest location of raw signal since we flipped the signal
MaximGordon	0:346a7fa07998	141	maxim_find_peaks( dx_peak_locs, &n_npks, n_dx, BUFFER_SIZE-HAMMING_SIZE, th1, 8, 5 );//peak_height, peak_distance, max_num_peaks
MaximGordon	0:346a7fa07998	142
MaximGordon	0:346a7fa07998	143	peakintervalSum =0;
MaximGordon	0:346a7fa07998	144	if (n_npks>=2){
MaximGordon	0:346a7fa07998	145	for (k=1; k<n_npks; k++)
MaximGordon	0:346a7fa07998	146	peakintervalSum += (dx_peak_locs[k] -dx_peak_locs[k -1] ) ;
MaximGordon	0:346a7fa07998	147	peakintervalSum =peakintervalSum/(n_npks-1);
MaximGordon	0:346a7fa07998	148	*n_heart_rate =(int32_t)( 6000/ peakintervalSum );// beats per minutes
MaximGordon	0:346a7fa07998	149	//prlongf(">>> n_heart_rate= %d \n", n_heart_rate) ;
MaximGordon	0:346a7fa07998	150	*ch_hr_valid = 1;
MaximGordon	0:346a7fa07998	151	}
MaximGordon	0:346a7fa07998	152	else {
MaximGordon	0:346a7fa07998	153	*n_heart_rate = -999;
MaximGordon	0:346a7fa07998	154	*ch_hr_valid = 0;
MaximGordon	0:346a7fa07998	155	}
MaximGordon	0:346a7fa07998	156
MaximGordon	0:346a7fa07998	157	for ( k=0 ; k<n_npks ;k++)
MaximGordon	0:346a7fa07998	158	ir_valley_locs[k]= dx_peak_locs[k] +HAMMING_SIZE /2;
MaximGordon	0:346a7fa07998	159
MaximGordon	0:346a7fa07998	160
MaximGordon	0:346a7fa07998	161	// raw value : RED(=y) and IR(=X)
MaximGordon	0:346a7fa07998	162	// we need to assess DC and AC value of ir and red PPG.
MaximGordon	0:346a7fa07998	163	for (k=0 ; k<n_ir_buffer_length ; k++ ) {
MaximGordon	0:346a7fa07998	164	n_x[k] = un_ir_buffer[k] ;
MaximGordon	0:346a7fa07998	165	n_y[k] = un_red_buffer[k] ;
MaximGordon	0:346a7fa07998	166	}
MaximGordon	0:346a7fa07998	167
MaximGordon	0:346a7fa07998	168	// find precise min near ir_valley_locs
MaximGordon	0:346a7fa07998	169	exact_ir_valley_locs_count =0;
MaximGordon	0:346a7fa07998	170	for ( k=0 ; k<n_npks ;k++){
MaximGordon	0:346a7fa07998	171	onlyOnce =1;
MaximGordon	0:346a7fa07998	172	m=ir_valley_locs[k];
MaximGordon	0:346a7fa07998	173	cMin= 16777216;//2^24;
MaximGordon	0:346a7fa07998	174	if (m+5 < BUFFER_SIZE-HAMMING_SIZE && m-5 >0){
MaximGordon	0:346a7fa07998	175
MaximGordon	0:346a7fa07998	176	for(i= m-5;i<m+5; i++)
MaximGordon	0:346a7fa07998	177	if (n_x[i]<cMin){
MaximGordon	0:346a7fa07998	178	if (onlyOnce >0){
MaximGordon	0:346a7fa07998	179	onlyOnce =0;
MaximGordon	0:346a7fa07998	180	}
MaximGordon	0:346a7fa07998	181	cMin= n_x[i] ;
MaximGordon	0:346a7fa07998	182	exact_ir_valley_locs[k]=i;
MaximGordon	0:346a7fa07998	183	}
MaximGordon	0:346a7fa07998	184	if (onlyOnce ==0) exact_ir_valley_locs_count ++ ;
MaximGordon	0:346a7fa07998	185	}
MaximGordon	0:346a7fa07998	186	}
MaximGordon	0:346a7fa07998	187	if (exact_ir_valley_locs_count <2 ){
MaximGordon	0:346a7fa07998	188	*n_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range
MaximGordon	0:346a7fa07998	189	*ch_spo2_valid = 0;
MaximGordon	0:346a7fa07998	190	return;
MaximGordon	0:346a7fa07998	191	}
MaximGordon	0:346a7fa07998	192	// 4 pt MA
MaximGordon	0:346a7fa07998	193	for(k=0; k< BUFFER_SIZE-MA4_SIZE; k++){
MaximGordon	0:346a7fa07998	194	n_x[k]=( n_x[k]+n_x[k+1]+ n_x[k+2]+ n_x[k+3])/(int32_t)4;
MaximGordon	0:346a7fa07998	195	n_y[k]=( n_y[k]+n_y[k+1]+ n_y[k+2]+ n_y[k+3])/(int32_t)4;
MaximGordon	0:346a7fa07998	196
MaximGordon	0:346a7fa07998	197	}
MaximGordon	0:346a7fa07998	198
MaximGordon	0:346a7fa07998	199	//using exact_ir_valley_locs , find ir-red DC andir-red AC for SPO2 calibration ratio
MaximGordon	0:346a7fa07998	200	//finding AC/DC maximum of raw ir * red between two valley locations
MaximGordon	0:346a7fa07998	201	ratioAverage =0;
MaximGordon	0:346a7fa07998	202	iRatioCount = 0;
MaximGordon	0:346a7fa07998	203
MaximGordon	0:346a7fa07998	204	for(k=0; k< 5; k++) ratio[k]=0;
MaximGordon	0:346a7fa07998	205	for (k=0; k< exact_ir_valley_locs_count; k++){
MaximGordon	0:346a7fa07998	206	if (exact_ir_valley_locs[k] > BUFFER_SIZE ){
MaximGordon	0:346a7fa07998	207	*n_spo2 = -999 ; // do not use SPO2 since valley loc is out of range
MaximGordon	0:346a7fa07998	208	*ch_spo2_valid = 0;
MaximGordon	0:346a7fa07998	209	return;
MaximGordon	0:346a7fa07998	210	}
MaximGordon	0:346a7fa07998	211	}
MaximGordon	0:346a7fa07998	212	// find max between two valley locations
MaximGordon	0:346a7fa07998	213	// and use ratio betwen AC compoent of Ir & Red and DC compoent of Ir & Red for SPO2
MaximGordon	0:346a7fa07998	214
MaximGordon	0:346a7fa07998	215	for (k=0; k< exact_ir_valley_locs_count-1; k++){
MaximGordon	0:346a7fa07998	216	yDCmax= -16777216 ;
MaximGordon	0:346a7fa07998	217	xDCmax= - 16777216;
MaximGordon	0:346a7fa07998	218	// printf("range=%d: %d\n ", exact_ir_valley_locs[k], exact_ir_valley_locs[k+1]);
MaximGordon	0:346a7fa07998	219	if (exact_ir_valley_locs[k+1]-exact_ir_valley_locs[k] >10){
MaximGordon	0:346a7fa07998	220	for (i=exact_ir_valley_locs[k]; i< exact_ir_valley_locs[k+1]; i++){
MaximGordon	0:346a7fa07998	221
MaximGordon	0:346a7fa07998	222	if (n_x[i]> xDCmax) {xDCmax =n_x[i];xDCmaxIdx =i; }
MaximGordon	0:346a7fa07998	223	if (n_y[i]> yDCmax) {yDCmax =n_y[i];yDCmaxIdx=i;}
MaximGordon	0:346a7fa07998	224	}
MaximGordon	0:346a7fa07998	225	yAC= (n_y[exact_ir_valley_locs[k+1]] - n_y[exact_ir_valley_locs[k] ] )*(yDCmaxIdx -exact_ir_valley_locs[k]); //red
MaximGordon	0:346a7fa07998	226	yAC= n_y[exact_ir_valley_locs[k]] + yAC/ (exact_ir_valley_locs[k+1] - exact_ir_valley_locs[k]) ;
MaximGordon	0:346a7fa07998	227
MaximGordon	0:346a7fa07998	228
MaximGordon	0:346a7fa07998	229	yAC= n_y[yDCmaxIdx] - yAC; // subracting linear DC compoenents from raw
MaximGordon	0:346a7fa07998	230	xAC= (n_x[exact_ir_valley_locs[k+1]] - n_x[exact_ir_valley_locs[k] ] )*(xDCmaxIdx -exact_ir_valley_locs[k]); // ir
MaximGordon	0:346a7fa07998	231	xAC= n_x[exact_ir_valley_locs[k]] + xAC/ (exact_ir_valley_locs[k+1] - exact_ir_valley_locs[k]);
MaximGordon	0:346a7fa07998	232	xAC= n_x[yDCmaxIdx] - xAC; // subracting linear DC compoenents from raw
MaximGordon	0:346a7fa07998	233	nume=( yAC *xDCmax)>>7 ; //prepare X100 to preserve floating value
MaximGordon	0:346a7fa07998	234	denom= ( xAC *yDCmax)>>7;
MaximGordon	0:346a7fa07998	235	if (denom>0 && iRatioCount <5 && nume != 0)
MaximGordon	0:346a7fa07998	236	{
MaximGordon	0:346a7fa07998	237	ratio[iRatioCount]= (nume100)/denom ; //formular is ( yAC xDCmax) / ( xAC *yDCmax) ;
MaximGordon	0:346a7fa07998	238	iRatioCount++;
MaximGordon	0:346a7fa07998	239	}
MaximGordon	0:346a7fa07998	240	}
MaximGordon	0:346a7fa07998	241
MaximGordon	0:346a7fa07998	242	// prlongf("ratio[%d]= %d exact_ir_valley_locs[k] =%d , exact_ir_valley_locs[%d] =%d \n",k, ratio[k] ,exact_ir_valley_locs[k] ,k+1, exact_ir_valley_locs[k+1] ) ;
MaximGordon	0:346a7fa07998	243	// prlongf("nume= %d ,denom= %d yAC = %d, xDCmax = %d, xAC= %d, yDCmax = %d\n",nume, denom, yAC ,xDCmax ,xAC ,yDCmax );
MaximGordon	0:346a7fa07998	244
MaximGordon	0:346a7fa07998	245	}
MaximGordon	0:346a7fa07998	246
MaximGordon	0:346a7fa07998	247	maxim_sort_ascend(ratio, iRatioCount);
MaximGordon	0:346a7fa07998	248	middleIdx= iRatioCount/2;
MaximGordon	0:346a7fa07998	249
MaximGordon	0:346a7fa07998	250	if (middleIdx >1)
MaximGordon	0:346a7fa07998	251	ratioAverage =( ratio[middleIdx-1] +ratio[middleIdx])/2; // use median
MaximGordon	0:346a7fa07998	252	else
MaximGordon	0:346a7fa07998	253	ratioAverage = ratio[middleIdx ];
MaximGordon	0:346a7fa07998	254
MaximGordon	0:346a7fa07998	255	if( ratioAverage>2 && ratioAverage <184){
MaximGordon	0:346a7fa07998	256	spo2calc= uch_spo2_table[ratioAverage] ;
MaximGordon	0:346a7fa07998	257	*n_spo2 = spo2calc ;
MaximGordon	0:346a7fa07998	258	ch_spo2_valid = 1;// float_SPO2 = -45.060ratioAverage* ratioAverage/10000 + 30.354 *ratioAverage/100 + 94.845 ; // for comparison with table
MaximGordon	0:346a7fa07998	259	}
MaximGordon	0:346a7fa07998	260	else{
MaximGordon	0:346a7fa07998	261	*n_spo2 = -999 ; // do not use SPO2 since signal ratio is out of range
MaximGordon	0:346a7fa07998	262	*ch_spo2_valid = 0;
MaximGordon	0:346a7fa07998	263	}
MaximGordon	0:346a7fa07998	264
MaximGordon	0:346a7fa07998	265
MaximGordon	0:346a7fa07998	266	}
MaximGordon	0:346a7fa07998	267
MaximGordon	0:346a7fa07998	268
MaximGordon	0:346a7fa07998	269	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 )
MaximGordon	0:346a7fa07998	270	/**
MaximGordon	0:346a7fa07998	271	* \brief Find peaks
MaximGordon	0:346a7fa07998	272	* \par Details
MaximGordon	0:346a7fa07998	273	* Find at most MAX_NUM peaks above MIN_HEIGHT separated by at least MIN_DISTANCE
MaximGordon	0:346a7fa07998	274	*
MaximGordon	0:346a7fa07998	275	* \retval None
MaximGordon	0:346a7fa07998	276	*/
MaximGordon	0:346a7fa07998	277	{
MaximGordon	0:346a7fa07998	278	maxim_peaks_above_min_height( n_locs, n_npks, n_x, n_size, n_min_height );
MaximGordon	0:346a7fa07998	279	maxim_remove_close_peaks( n_locs, n_npks, n_x, n_min_distance );
MaximGordon	0:346a7fa07998	280	n_npks = min( n_npks, n_max_num );
MaximGordon	0:346a7fa07998	281	}
MaximGordon	0:346a7fa07998	282
MaximGordon	0:346a7fa07998	283	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 )
MaximGordon	0:346a7fa07998	284	/**
MaximGordon	0:346a7fa07998	285	* \brief Find peaks above n_min_height
MaximGordon	0:346a7fa07998	286	* \par Details
MaximGordon	0:346a7fa07998	287	* Find all peaks above MIN_HEIGHT
MaximGordon	0:346a7fa07998	288	*
MaximGordon	0:346a7fa07998	289	* \retval None
MaximGordon	0:346a7fa07998	290	*/
MaximGordon	0:346a7fa07998	291	{
MaximGordon	0:346a7fa07998	292	int32_t i = 1, width;
MaximGordon	0:346a7fa07998	293	*n_npks = 0;
MaximGordon	0:346a7fa07998	294
MaximGordon	0:346a7fa07998	295	while (i < n_size-1){
MaximGordon	0:346a7fa07998	296	if (n_x[i] > n_min_height && n_x[i] > n_x[i-1]){ // find left edge of potential peaks
MaximGordon	0:346a7fa07998	297	width = 1;
MaximGordon	0:346a7fa07998	298	while (i+width < n_size && n_x[i] == n_x[i+width]) // find flat peaks
MaximGordon	0:346a7fa07998	299	width++;
MaximGordon	0:346a7fa07998	300	if (n_x[i] > n_x[i+width] && (*n_npks) < 15 ){ // find right edge of peaks
MaximGordon	0:346a7fa07998	301	n_locs[(*n_npks)++] = i;
MaximGordon	0:346a7fa07998	302	// for flat peaks, peak location is left edge
MaximGordon	0:346a7fa07998	303	i += width+1;
MaximGordon	0:346a7fa07998	304	}
MaximGordon	0:346a7fa07998	305	else
MaximGordon	0:346a7fa07998	306	i += width;
MaximGordon	0:346a7fa07998	307	}
MaximGordon	0:346a7fa07998	308	else
MaximGordon	0:346a7fa07998	309	i++;
MaximGordon	0:346a7fa07998	310	}
MaximGordon	0:346a7fa07998	311	}
MaximGordon	0:346a7fa07998	312
MaximGordon	0:346a7fa07998	313
MaximGordon	0:346a7fa07998	314	void maxim_remove_close_peaks( int32_t n_locs, int32_t n_npks, int32_t *n_x, int32_t n_min_distance )
MaximGordon	0:346a7fa07998	315	/**
MaximGordon	0:346a7fa07998	316	* \brief Remove peaks
MaximGordon	0:346a7fa07998	317	* \par Details
MaximGordon	0:346a7fa07998	318	* Remove peaks separated by less than MIN_DISTANCE
MaximGordon	0:346a7fa07998	319	*
MaximGordon	0:346a7fa07998	320	* \retval None
MaximGordon	0:346a7fa07998	321	*/
MaximGordon	0:346a7fa07998	322	{
MaximGordon	0:346a7fa07998	323
MaximGordon	0:346a7fa07998	324	int32_t i, j, old_npks, dist;
MaximGordon	0:346a7fa07998	325
MaximGordon	0:346a7fa07998	326	/* Order peaks from large to small */
MaximGordon	0:346a7fa07998	327	maxim_sort_indices_descend( n_x, n_locs, *n_npks );
MaximGordon	0:346a7fa07998	328
MaximGordon	0:346a7fa07998	329	for ( i = -1; i < *n_npks; i++ ){
MaximGordon	0:346a7fa07998	330	old_npks = *n_npks;
MaximGordon	0:346a7fa07998	331	*n_npks = i+1;
MaximGordon	0:346a7fa07998	332	for ( j = i+1; j < old_npks; j++ ){
MaximGordon	0:346a7fa07998	333	dist = n_locs[j] - ( i == -1 ? -1 : n_locs[i] ); // lag-zero peak of autocorr is at index -1
MaximGordon	0:346a7fa07998	334	if ( dist > n_min_distance \|\| dist < -n_min_distance )
MaximGordon	0:346a7fa07998	335	n_locs[(*n_npks)++] = n_locs[j];
MaximGordon	0:346a7fa07998	336	}
MaximGordon	0:346a7fa07998	337	}
MaximGordon	0:346a7fa07998	338
MaximGordon	0:346a7fa07998	339	// Resort indices longo ascending order
MaximGordon	0:346a7fa07998	340	maxim_sort_ascend( n_locs, *n_npks );
MaximGordon	0:346a7fa07998	341	}
MaximGordon	0:346a7fa07998	342
MaximGordon	0:346a7fa07998	343	void maxim_sort_ascend(int32_t *n_x, int32_t n_size)
MaximGordon	0:346a7fa07998	344	/**
MaximGordon	0:346a7fa07998	345	* \brief Sort array
MaximGordon	0:346a7fa07998	346	* \par Details
MaximGordon	0:346a7fa07998	347	* Sort array in ascending order (insertion sort algorithm)
MaximGordon	0:346a7fa07998	348	*
MaximGordon	0:346a7fa07998	349	* \retval None
MaximGordon	0:346a7fa07998	350	*/
MaximGordon	0:346a7fa07998	351	{
MaximGordon	0:346a7fa07998	352	int32_t i, j, temp;
MaximGordon	0:346a7fa07998	353	for (i = 1; i < n_size; i++) {
MaximGordon	0:346a7fa07998	354	temp = n_x[i];
MaximGordon	0:346a7fa07998	355	for (j = i; j > 0 && temp < n_x[j-1]; j--)
MaximGordon	0:346a7fa07998	356	n_x[j] = n_x[j-1];
MaximGordon	0:346a7fa07998	357	n_x[j] = temp;
MaximGordon	0:346a7fa07998	358	}
MaximGordon	0:346a7fa07998	359	}
MaximGordon	0:346a7fa07998	360
MaximGordon	0:346a7fa07998	361	void maxim_sort_indices_descend( int32_t n_x, int32_t n_indx, int32_t n_size)
MaximGordon	0:346a7fa07998	362	/**
MaximGordon	0:346a7fa07998	363	* \brief Sort indices
MaximGordon	0:346a7fa07998	364	* \par Details
MaximGordon	0:346a7fa07998	365	* Sort indices according to descending order (insertion sort algorithm)
MaximGordon	0:346a7fa07998	366	*
MaximGordon	0:346a7fa07998	367	* \retval None
MaximGordon	0:346a7fa07998	368	*/
MaximGordon	0:346a7fa07998	369	{
MaximGordon	0:346a7fa07998	370	int32_t i, j, temp;
MaximGordon	0:346a7fa07998	371	for (i = 1; i < n_size; i++) {
MaximGordon	0:346a7fa07998	372	temp = n_indx[i];
MaximGordon	0:346a7fa07998	373	for (j = i; j > 0 && n_x[temp] > n_x[n_indx[j-1]]; j--)
MaximGordon	0:346a7fa07998	374	n_indx[j] = n_indx[j-1];
MaximGordon	0:346a7fa07998	375	n_indx[j] = temp;
MaximGordon	0:346a7fa07998	376	}
MaximGordon	0:346a7fa07998	377	}
MaximGordon	0:346a7fa07998	378

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	09 Jun 2021
Imports:	6
Forks:	0
Commits:	6
Dependents:	0
Dependencies:	1
Followers:	1

algorithm/algorithm.cpp@1:e88f22c6c1b0, 2016-04-20 (annotated)

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