Im trying to compress an image using huffman coding "no built in func allowed"

I've generated the codes for each probability but i cant encode them in the image matrix A, as unit8 cant be transformed to cell matrix. any help please?

< clc; clear all; global CODE A1 = imread('fig2.jpg');

 A1=rgb2gray(A1);

 A1=imresize(A1,[48 48]);

%imshow(A1)
[M, N]=size(A1);
A = A1(:);
count = imhist(A);
p = count / numel(A);
CODE = cell(length(p), 1);
s = cell(length(p), 1);


for i = 1:length(p) % Generate a starting tree with symbol nodes 1, 2, 3, ... to 
                    % reference the symbol probabilities.
   s{i} = i ;
end
while numel(s) > 2
   [p, i] = sort(p);    % Sort the symbol probabilities
   p(2) = p(1) + p(2);  % Merge the 2 lowest probabilities
   p(1) = [];           % and prune the lowest one

   s = s(i);            % Reorder tree for new probabilities
   s{2} = {s{1}, s{2}}; % and merge & prune its nodes
   s(1) = [] ;            % to match the probabilities
end
 makecode(s, [])


 for i = 1:numel(CODE)
    c = CODE{i};
    t = c; c(c=='1') = '0'; c(t=='0') = '1';
    CODE{i} = c;

 end
%----------------------
function makecode(sc, codeword)
% Scan the nodes of a Huffman source reduction tree recursively to
% generate the indicated variable length code words.

% Global variable surviving all recursive calls
global CODE                           

if isa(sc,'cell')                    % For cell array nodes,
   makecode(sc{1}, [codeword 0]);    % add a 0 if the 1st element
   makecode(sc{2}, [codeword 1]);    % or a 1 if the 2nd
else                                 % For leaf (numeric) nodes,
   CODE{sc} = char('0' + codeword);  % create a char code string
end>