Press.m

% Helper function called by NCD 
% uses libbz2.dll to bzip Compress V1,V2
% Returns the size in bytes of the compressed data
% 
function nBytes = Press(V1,V2)

persistent  lib
if ~libisloaded('bzlib')
    warning('off','MATLAB:loadlibrary:StructTypeExists');
    warning('off','MATLAB:loadlibrary:parsewarnings');
    warning('off','MATLAB:loadlibrary:TypeNotFoundForStructure');
    thisFile=fileparts(mfilename('fullpath'));
    path(path,fullfile(thisFile,'../../lib'));
    if isunix        
        [nf,w]=loadlibrary('bzip2.so','bzlib.h','alias', 'bzlib');
    else
        loadlibrary bz2dll.dll bzlib.h  alias bzlib
    end
end

if iscell(V1)
    V1=cell2mat(V1);
end

if iscell(V2)
    V2=cell2mat(V2);
end

vv=combineString(V1,V2);

sz=length(vv(:));
dsz=sz+1024;
dest= mat2str(zeros(dsz,1));
pstr=libpointer('cstring', vv);
pdest=libpointer('cstring', dest);
pdsz = libpointer('uint32Ptr',dsz);

rval=calllib('bzlib', 'BZ2_bzBuffToBuffCompress', pdest,pdsz,vv,sz,9,0,30);
if rval
    disp 'ACK! bad return from bzip'
    rval
end
nBytes=double(get(pdsz, 'Value'));

function vv=combineString(V1,V2)

s1=prepareString(V1);
s2=prepareString(V2);

vv=[s1 ';' s2];

function s=prepareString(v)
if isempty(v)
    s='';
    return
end
if ischar(v)
    s=v;
    return
end
s=mat2str(v);
if length(v)>1
    s=s(2:end-1);
end