huffmanenco.m

MATLAB编写的huffman编解码程序

function enco = huffmanEnco(sig,dict)
%    
%    Encodes the input signal, sig, based on the code dictionary, dict. 
%    The code dictionary is generated using the huffmanDict function.
%--------------------------------------------------------------------------

% Make sure that the input symbols are in a cell array format
if (~iscell(sig) )
	[m,n] = size(sig);
	sig = mat2cell(sig, ones(1,m), ones(1,n) );
end

% Preallocate memory for enco
maxSize = 0;
dictLength = size(dict,1);
for i = 1 : dictLength
    tempSize = size(dict{i,2},2);
    if (tempSize > maxSize)
        maxSize = tempSize;
    end
end
enco = zeros(1, length(sig)*maxSize);

% Search the dictionary sequentially to find the code for the given signal
idxCode = 1;
for i = 1 : length(sig)
    tempcode = [];
    for j = 1 : dictLength
        if( sig{i} == dict{j,1} )
            tempcode = dict{j,2};
            break;
        end
    end 
    lenCode = length(tempcode);
    enco(idxCode : idxCode+lenCode-1) = tempcode;
    idxCode = idxCode + lenCode;
end

% Strip off the unused vector elements
enco = enco(1:idxCode-1);