how to get the compressed image from huffman

i am using huffman dictioanry to encode n decode

how do i get the compressed image entropy, average length

this is my code

    clc
    clear all
    inputImage=imread('cameraman.bmp');
    [row col] =size(inputImage);
    quantizedValue=10;
    QuantizedImage= inputImage/quantizedValue;
    QuantizedImage=round(QuantizedImage);
    %QuantizedImage=uint8(QuantizedImage);
    %ImageArray=reshape(QuantizedImage,[1 row*col]);
    GrayValueDict=(1:256);
    ProbDict=zeros(1,256);
    %{
    for(i=0:255)
       GrayValueDict(i+1)=i; 
    end
        %}   
    for(i=0:255)
          for(r=1:row)
              for(c=1:col)
                  if(i==QuantizedImage(r,c))
                     ProbDict(i)=ProbDict(i)+1;
                  end
              end
          end
      end
    ProbDict= ProbDict/(row*col)   ;
    %ProbDict= round(ProbDict,3);
    dict = huffmandict(GrayValueDict,ProbDict,5);
    sig=reshape(QuantizedImage,[1 row*col]);
    hcode = huffmanenco(sig,dict);
    dhsig = huffmandeco(hcode,dict);
    out= reshape(dhsig, [256 256]);
    out=out*10;
    subplot(1,2,1);
    imshow(inputImage,[]);
    subplot(1,2,2);
    imshow(out,[]);
    isequal(sig,dhsig);