matlab把图片转为base64

function [base64string,base64string_len] = base64file(file)
fid = fopen(file,'rb');
bytes = fread(fid);
fclose(fid);
base64string_len = size(bytes,1);
encoder = org.apache.commons.codec.binary.Base64;
base64string = char(encoder.encode(bytes))';
end