from Arithemetic Coding by Ravi Lakkundi
Program to compress text using arithmetic coding.

t=input_bit
function t=input_bit

format long
global fid bits_to_go garbage_bits buffer code_value_bits
persistent ii
if(isempty(ii)),ii=1;end

if(bits_to_go==0)
    buffer=fread(fid,1);
    if feof(fid)
        garbage_bits=garbage_bits+1;
        if garbage_bits > code_value_bits - 2
            disp(' INPUT ERROR ');
        end
    end
    bits_to_go=8;
end

t=bitand(buffer,1);
buffer=fix(buffer*2^-1);
bits_to_go=bits_to_go-1;

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