function clipdata = cclip(xin,cliptype,clpercent)
%  This function applies various form of clipping to the input signal
%  based a percentage of its peak values.
%
%     [clipdata] = cclip(xin,cliptype,clpercent)
%
%  inputs:
%  xin      => Vector of input signal values
%  cliptype => a string indicating which cliptype to apply
%          'clc' = Soft Center Clip:
%          C[x(n)]=x(n)-Cl for (x(n)>=Cl), 0 for (|x(n)|<Cl),  and x(n)+Cl for (x(n)<=-Cl)
%          'clp' = Hard Center Clip:
%          C[x(n)]=x(n) for (|x(n)|>=Cl), and 0 for (|x(n)|<Cl)
%          'sig' = Hard Limit Center Clip:
%          C[x(n)]= 1 for (|x(n)|>=Cl), 0 for (|x(n)|<Cl), and   -1 for (x(n)<=-Cl)
%  clpercent => percentage of minimum of maximum positive or negative going peak values
%               clipping level must be between 0 < cl < 1
%
%   Written by Tim Black, updated by Kevin D. Donohue (donohue@engr.uky.edu) Jan 2006


% The Clipping level, cl, is set to the percentage of the smaller magnitude of the 
% positive and negative peaks 
if clpercent > 1 | clpercent < 0
    error('Precent of signal for clip threshold should be between 0 and 1')
end
effmag=min([abs(max(xin)),abs(min(xin))]);

cl=clpercent*effmag(1);
% Center clip xwin (the current window of xin) according to argument cliptype: 
clipdata=zeros(1,length(xin));  %  Initialize output to zeros
ind1=find(xin>=cl);     %  find all positive points greater than clip threshold 
ind2=find(xin<=-cl);    %  fild all negative points with magnitudes greater than clip threshold

if cliptype=='clc'   %  Center soft clip
   clipdata(ind1)=xin(ind1)-cl;  %  Reduce amplitude by clip threshold (for positive values)
   clipdata(ind2)=xin(ind2)+cl;  %  Reduce amplitude by clip threshold (for negative values)
elseif cliptype=='clp' %  Center hard clip
   clipdata(ind1)=xin(ind1);  % Pass positive values greater than threshold 
   clipdata(ind2)=xin(ind2); % Pass negative values with magnitudes greather than threshold
elseif cliptype == 'sig'   %  Hard limit center clip
   clipdata(ind1)=1;  %  Set postive values to 1;
   clipdata(ind2)=-1; %  Set negative values to -1;
else
    error('Clip Type not specified!  Use strings clc, clp, sig, for soft, hard, or hard limit center clip.')
end