function [callnumber, part, begframe, lenframe, begsam, lensam]=wheremg(begmg, lenmg)
% Syntax: [call, part, begframe, lenframe, begsam, lensam]=wheremg(begmg, lenmg);
%
% function for multigram finding in the original database. 
% Before 1st call to that function , wheremginit MUST BE EXECUTED filling 
% some global variables.
%
% begmg - beginning of multigram in the big chain
% lenmg - length of multigram
% call  - call number, where is this multigram
% part  - part number (within the call)
% begframe - beginning frame of that mg. (within the call).
% lenframe - length of that mg. (in frames)
% begsam   - beginning of that mg. (in samples)
% lensam   - length of that mg. (in samples)

% global vars got from wheremginit:

global wmg_liste wmg_call_begins_in_targets wmg_calls wmg_path

%%% determine the call.

callindex = find( begmg >= wmg_call_begins_in_targets(1:wmg_calls) & ...
                  begmg < wmg_call_begins_in_targets(2:wmg_calls+1) );
if (size(callindex) ~= [1 1] )
  disp ('can not find the call corresponding to that multigram');
end  
begcall = wmg_call_begins_in_targets (callindex);
callnumber = wmg_liste(callindex);

%%% get the beginning relative to this call

begmgincall = begmg - begcall;

%%% load the files necessary for call - at first, the IFLIM FILE
%---------------------------------------------------------------
nameiflim=[wmg_path int2str(callnumber) '.iflim'];
iflim=readparam(nameiflim, [3, inf], 'long');

phibegins=iflim(1,:);
phiends=iflim(2,:);
phigrav=iflim(3,:);
philengths=phiends-phibegins;

% then PLIM file
%---------------

nameplim=[wmg_path int2str(callnumber) '.plim'];
plimfile=fopen(nameplim, 'r');
plim=fscanf(plimfile, '%d', [2 inf]);
fclose(plimfile);
  
pbegins=plim(1,:);
plengths=plim(2,:);
parts=length(plengths);
%pbegins
%plengths

%%% now, put it all together
%-----------------------------------

% get the no of part and check, if the mg. does not "cross" parts

partnumber=max (find (begmgincall >= pbegins)) - 1;  % in C indexing
if (begmgincall + lenmg > pbegins(partnumber+1) + plengths(partnumber+1) ),
  error ('this is bad. Multigram goes over the part border.');
end  

% begmgincall and lenmg can be used directly to index the interpol functions
%============================================================================
% IMPORTANT PART: how to choose the beg. and end of a segment ?
% Possibilities:
% 1) beginning of 1st, end of last interpol function
% 2) center of gravity of 1st, center of gravity of last interepol fun
%       (bad for just uni-grams)
% 3) beginning: average of the beginning of 1st fun with the end of previous fun
%    end:       average of the end of last fun with the beginning of next fun.
%    for 1st function in the beginning of part - beg. of 1st function
%    for last fun in the end of part - end of last fun.

bmm=begmgincall + 1 ; 	% for Matlab
%%% 1) 
%begframe=phibegins(bmm);
%endframe=phiends(bmm + lenmg - 1);

%%% 2) 
%begframe=phigrav(bmm);	
%endframe=phigrav(bmm + lenmg - 1);

%%% 3) 
partbegin=pbegins(partnumber+1); partlength=plengths(partnumber+1);
if begmgincall > partbegin,	% not first function in part
  begframe=round( (phibegins(bmm) + phiends(bmm-1)) / 2);
else				% 1st function in part
  begframe=phibegins(bmm);
end
  
if begmgincall < partbegin + partlength -1,	% not last function in part 
  endframe = round ( (phiends(bmm + lenmg - 1) + phibegins(bmm + lenmg)) / 2);
else 						% it is the last
  endframe=phiends(bmm + lenmg - 1);     
end
% -----------

lenframe=endframe-begframe+1;

% and in samples:
begsam=begframe * 80;
endsam=endframe * 80 + 159;
lensam=endsam-begsam+1;

%disp('call, part, begframe, lenframe, begsam, lensam');
%[int2str(callnumber) ' ' int2str(partnumber) ' '  int2str(begframe) ' '  int2str(lenframe) ...
%  ' ' int2str(begsam) ' '  int2str(lensam)]
 
disp([int2str(callnumber)  ' ' int2str(begsam) ' '  int2str(lensam)]);