Just look at the definition of the function below, all parameters are explained there. In meantime we have a firmware fix to avoid the spikes inside the chip, but I have not yet found time to update the evaluation board.
void DRSBoard::RemoveSymmetricSpikes(short **wf, int nwf,
short diffThreshold, int spikeWidth,
short maxPeakToPeak, short spikeVoltage,
// Remove a specific kind of spike on DRS4.
// This spike has some features,
// - Common on all the channels on a chip
// - Constant heigh and width
// - Two spikes per channel
// - Symmetric to cell #0.
// This is not general purpose spike-removing function.
// wf : Waveform data. cell#0 must be at bin0,
// and number of bins must be kNumberOfBins.
// nwf : Number of channels which "wf" holds.
// diffThreshold : Amplitude threshold to find peak
// spikeWidth : Width of spike
// maxPeakToPeak : When peak-to-peak is larger than this, the channel
// is not used to find spikes.
// spikeVoltage : Amplitude of spikes. When it is 0, it is calculated in this function
// from voltage difference from neighboring bins.
// nTimeRegionThreshold : Requirement of number of time regions having spike at common position.
// Total number of time regions is 2*"nwf".