function q=zigzag(in)
%zigzag掃描函數(shù) 
%% 函數(shù)體
[n,m]=size(in);

if( (n~=8) & (m~=8))
   error('輸入不是 8*8 矩陣格式');
end

zig = [ 0, 1, 8, 16, 9, 2, 3, 10, ...
        17, 24, 32, 25, 18, 11, 4, 5, ...
        12, 19, 26, 33, 40, 48, 41, 34, ...
        27, 20, 13, 6, 7, 14, 21, 28, ...
        35, 42, 49, 56, 57, 50, 43, 36, ...
        29, 22, 15, 23, 30, 37, 44, 51, ...
        58, 59, 52, 45, 38, 31, 39, 46, ...
        53, 60, 61, 54, 47, 55, 62, 63];
zig = zig + 1;  
in2= reshape(in,1,64); 
q = in2(zig);