source: fact/tools/rootmacros/SpikeRemoval.C@ 17689

#include "SpikeRemoval.h"

#include <iostream>
using namespace std;

// compute the mean of the left and right neighbors of a channel
vector<float> * computeN1mean( vector<float> &src)
{
    vector<float> * dest = new vector<float>;

    dest->push_back(src[1]);

    for(unsigned int i = 1; i < src.size() - 1; i++){
/*        if (i == 0){ // use right sample es mean
            N1mean[i] = Ameas[i+1];
        }
        else if ( i == Samples-1 ){ //use left sample as mean
            N1mean[i] = Ameas[i-1];
        }
        else{
            N1mean[i] = ( Ameas[i-1] + Ameas[i+1] ) / 2.;
        }
*/
        dest->push_back( ( src[i-1] + src[i+1] ) / 2. );
    }

    dest->push_back(src[src.size() - 1]);
    return dest;
} // end of computeN1mean computation

void removeSpikes(
    vector<float> &src,
    vector<float> &dest,
    const float CandidateTHR,
    const float nextDiffTHR,
    const float nextNextDiffTHR
){
    //vector with Mean values of both neighbor samples of a sample
    vector<float> * NextNeighborMean = computeN1mean(src);

    if (src.size() != NextNeighborMean->size())
    {
        //TODO .. if verbositylevel .. say something, use the return code to tell the caller..
        dest.clear();
    }
    dest = src;

    float diff, nextDiff, nextNextDiff;

// find the spike and replace it by mean value of neighbors
    for (unsigned int i = 0; i < src.size(); i++) {

        //calculate difference of sample value and average of both it's neighbors
        diff = src[i] - (*NextNeighborMean)[i];

        //compare sample value to average of both neighbors
        if ( diff < CandidateTHR ){ // a spike candidate
            // check consistency with a single channel spike

            // check if the nectneighbor is a spike candidate too
            if ( src[i+2] - ( src[i] + src[i+3] )/2. > 10. )
            {
                dest[i+1]   = ( src[i] + src[i+3] )/2.;
                dest[i+2]   = ( src[i] + src[i+3] )/2.;

                i           = i + 3;
            }
            else
            {
                //calculate difference of sample value and average of both it's neighbors of next sample
                nextDiff        = src[i+1] - (*NextNeighborMean)[i+1];
                //calculate difference of sample value and average of both it's neighbors of over-next sample
                nextNextDiff    = src[i+2] - (*NextNeighborMean)[i+2];

                if ( ( nextDiff > nextDiffTHR * diff ) && ( nextNextDiff < nextNextDiffTHR ) )
                {
                    dest[i+1]                   = (*NextNeighborMean)[i+1];
                    (*NextNeighborMean)[i+2]    = (src[i+1] - src[i+3] / 2.);

                    i = i + 2;//do not care about the next sample it was the spike
                }
                // treatment for the end of the pipeline must be added !!!
            }
        }
    } // end of spike search and correction
    delete NextNeighborMean;
    return;
}