This is C++ algorithm, and convolution kernel generator with MATLAB
1.
Open "fir coeff gen.m" file with MATLAB
2.
Setting parameter(Fc, Fs, N, window function) and coefficient type(LPF, HPF, BPF)
3.
Gen coefficient file N.txt, N = taps
Unit impulse response of fir filter
C++ array format for example :
167.txt
0.0015893,0.0018612,0.002026,0.0020755,0.0020047,0.0018123,0.0015006,0.0010755,0.00054665,-7.3053e-05,-0.00076747,-0.0015178,-0.0023028,-0.0030999,-0.0038851,-0.0046342,-0.0053232,-0.0059295,-0.0064317,-0.0068114,-0.0070528,-0.0071441,-0.0070774,-0.0068492,-0.006461,-0.0059188,-0.0052337,-0.0044212,-0.0035014,-0.0024983,-0.0014392,-0.00035412,0.00072491,0.0017648,0.0027323,0.0035948,0.0043216,0.0048847,0.0052594,0.0054256,0.0053686,0.005079,0.0045542,0.003798,0.0028211,0.0016411,0.00028227,-0.0012247,-0.0028434,-0.0045321,-0.0062451,-0.007933,-0.0095444,-0.011027,-0.012328,-0.013398,-0.014187,-0.014654,-0.014757,-0.014466,-0.013756,-0.012609,-0.011018,-0.0089831,-0.0065162,-0.0036373,-0.00037597,0.0032289,0.0071303,0.011273,0.015597,0.020035,0.024516,0.028966,0.033312,0.037479,0.041395,0.044991,0.048203,0.050974,0.053254,0.055001,0.056184,0.056781,0.056781,0.056184,0.055001,0.053254,0.050974,0.048203,0.044991,0.041395,0.037479,0.033312,0.028966,0.024516,0.020035,0.015597,0.011273,0.0071303,0.0032289,-0.00037597,-0.0036373,-0.0065162,-0.0089831,-0.011018,-0.012609,-0.013756,-0.014466,-0.014757,-0.014654,-0.014187,-0.013398,-0.012328,-0.011027,-0.0095444,-0.007933,-0.0062451,-0.0045321,-0.0028434,-0.0012247,0.00028227,0.0016411,0.0028211,0.003798,0.0045542,0.005079,0.0053686,0.0054256,0.0052594,0.0048847,0.0043216,0.0035948,0.0027323,0.0017648,0.00072491,-0.00035412,-0.0014392,-0.0024983,-0.0035014,-0.0044212,-0.0052337,-0.0059188,-0.006461,-0.0068492,-0.0070774,-0.0071441,-0.0070528,-0.0068114,-0.0064317,-0.0059295,-0.0053232,-0.0046342,-0.0038851,-0.0030999,-0.0023028,-0.0015178,-0.00076747,-7.3053e-05,0.00054665,0.0010755,0.0015006,0.0018123,0.0020047,0.0020755,0.002026,0.0018612,0.0015893
4.
Copy coefficient to first parameter(double *coefficients) of FIR-class construct, and setting second parameter(unsigned number_of_taps) taps+1(e.g N=167 + 1)
5.
result = FIR.filter(signal);
example :
> g++ -o2 -o main main.cpp FIR.cpp --std=c++11
./main ./ECG\ ATM\ 104\ Special\ case.txt output.txt
ECG Database from PhysioBank ATM
https://www.physionet.org/cgi-bin/atm/ATM