how can i do huffman encoding in image compression

hi,i am doing lossy image compression using discrete cosine transform i had done all the steps of the compression(dct then quantization then zigzag scan) now i have a vector and i want to do huffman encoding i know that the code as follows

 [dict,avglen] = huffmandict(symbols,p) 
 comp = huffmanenco(sig,dict)

i am asking now how to get the symbol and p(probability) from the large vector that i have to do the encoding

Answer 1

If your vector is uint8() then one way of doing it is

symbols = unique(YourVector(:));
counts = hist(YourVector(:), symbols);
p = double(counts) ./ sum(counts);

This is not the only way.