msbaseremove.m

   
  MSBASEREMOVE performs a baseline correction over a set of MS spectra.
  YOUT = MSBASEREMOVE(Y,MASK) corrects the signal amplification produced by the chemical compounds of the matrix used to fix a biological sample in a MS experiment. Y is a matrix where each row corresponds to one MZ reading and each column maps a sample run. YOUT will have the same dimensions as Y but with corrected values.
  The baseline correction is tackled by means of a top-hat filter. MASK is the filtering mask of the filter and should be a column array of length 200  400. MASK must be composed of mainly ones, with some zero values in the extreme indexes. Default value is configured as [0; ones(298,1); 0].
  The top-hat filter constitutes a very well known morphological operator within the image domain. It was firstly borrowed to the MS data analysis by [Sauve & Speed, 2004] and other authors have proposed slight modifications to the original filter for the same baseline correction purpose [Prados et al., 2006 and Noy & Fasulo, 2007].