ECG.zip_ECG_ecg 单片机_单片机心电图_滤波算法

#include "config.h" #include "Ecgini.h" //extern int16 g_FilterData[ DISP_MAX_LEN ]; //extern int16 g_uCurData[ DISP_MAX_LEN ]; // 当前采集的心电图数据，压缩格式，17字节为一个点 extern uint32 g_DispWOff; extern int32 g_Src320Off; extern GATHERPARA g_PrnPara; int16* g_SrcDat; // 滤波参数 static float b_50[3] = { 7.369218750000e+002F, -1.401718750000e+003F, 7.369218750000e+002F}; //float gain_50=1.354008913040e-003F; static float a_50[3] = { 1.354008913040e-003F, -1.897979736328e+000F, 9.956054687500e-001F}; float w1_50[MAX_DAO]; float w2_50[MAX_DAO]; static float b_05[3] = { 1, -1.96529007, 1 }; static float a_05[3] = { 0.000100485, -1.997929215, 0.9979330897 }; double w1_05[ MAX_DAO ]; double w2_05[ MAX_DAO ]; float g_gain5 = 0.000100485; static char b_25[ 3 ] = { 1, 2, 1 }; static float a_25[3] = { 0.00554272, -1.778631806, 0.8008026481 }; float w1_25[ MAX_DAO ]; float w2_25[ MAX_DAO ]; static char b_35[ 3] = { 1, 2, 1}; //static float gain=0.0104324; static float a_35[ 3] = { 0.0104324, -1.690996408, 0.7327260375}; float w1_35[ MAX_DAO ]; float w2_35[ MAX_DAO ]; // 实时滤波 double g_temp; /* scratch variable */ // 滤交流 50HZ void filter_Bandstop50( int16* pIn, int16* pOut ) { uint8 i; for( i = 0; i < MAX_DAO; i++) { g_temp = ( a_50[0] * pIn[ i ] - a_50[1] * w1_50[ i ] - a_50[2] * w2_50[i] ); pOut[ i ] = ( b_50[0] * g_temp + b_50[1] * w1_50[ i ] + b_50[2] * w2_50[i] ); w2_50[ i ] = w1_50[i]; w1_50[ i ] = g_temp; } } // 滤基线 0.5Hz void filter_highpass05 ( int16* pIn, int16* pOut ) { uint8 i; double temp; for ( i=0; i < MAX_DAO; i++) { temp = ( a_05[0] * pIn[ i ] - a_05[1] * w1_05[ i ] - a_05[2] * w2_05[i] ) ; pOut[ i ] = ( b_05[0] * temp + b_05[1] * w1_05[ i ] + b_05[2] * w2_05[i] ); if( g_SrcDat != NULL ) pOut[ i ] = g_SrcDat[ i ] - pOut[ i ]; w2_05[ i ] = w1_05[i]; w1_05[ i ] = temp; } } void filter_lowpass25 ( int16* pIn, int16* pOut ) { uint8 i; for ( i=0; i < MAX_DAO; i++) { g_temp = ( a_25[0] * pIn[ i ] - a_25[1] * w1_25[ i ] - a_25[2] * w2_25[i] ); pOut[ i ] = ( b_25[0] * g_temp + b_25[1] * w1_25[ i ] + b_25[2] * w2_25[i] ); w2_25[ i ] = w1_25[i]; w1_25[i] = g_temp; } } void filter_lowpass35 ( int16* pIn, int16* pOut ) { uint8 i; for ( i=0; i < MAX_DAO; i++) { g_temp = ( a_35[0] * pIn[ i ] - a_35[1] * w1_35[ i ] - a_35[2] * w2_35[i] ); pOut[ i ] = ( b_35[0] * g_temp + b_35[1] * w1_35[ i ] + b_35[2] * w2_35[i] ); w2_35[ i ] = w1_35[i]; w1_35[i] = g_temp; } } void FilterInit( void ) { uint8 i=0; for( i=0; i< MAX_DAO; i++ ) { w1_50[i] = 0; w2_50[i] = 0; w1_05[i] = 0; w2_05[i] = 0; w1_25[i] = 0; w2_25[i] = 0; w1_35[i] = 0; w2_35[i] = 0; } } /************************************************ * Filter( ) 滤波 * **************************************************/ void Filter( int16* pInD, int16* pOutD ) { uint8 i; int16* pIn = &pInD[ g_DispWOff ]; int16* pOut = &pOutD[ g_DispWOff ]; if( g_Src320Off >= 0 ) g_SrcDat = &pInD[ g_Src320Off ]; else g_SrcDat = NULL; if( g_PrnPara.filter ) { if( g_PrnPara.filter & FILTER_JX ) // 基线 { filter_highpass05( pIn, pOut ); pIn = pOut; } if( g_PrnPara.filter & FILTER_25 ) { filter_lowpass25( pIn, pOut ); } else if( g_PrnPara.filter & FILTER_35 ) { filter_lowpass35( pIn, pOut ); } else if( g_PrnPara.filter & FILTER_JL ) // 交流 { filter_Bandstop50( pIn, pOut ); } } else { for ( i=0; i < MAX_DAO; i++) pOut[ i ] = pIn[ i ]; } }