base64-encode.js

function encodeImage(imageUrl, callback) {
    var URL = require('url'),
        sURL = imageUrl,
        oURL = URL.parse(sURL),
        http = require('http');
	
	var request = http.request({method:'GET', path:oURL.pathname, host: oURL.hostname, port:80});
	
	request.end();
	
    request.on('response', function (response) {
        var type = response.headers["content-type"],
            prefix = "data:" + type + ";base64,",
            body = "";
		
		response.setEncoding('binary');
		
        response.on('end', function () {
            var base64 = new Buffer(body, 'binary').toString('base64'),
                data = prefix + base64;
            return callback(data);
        });
		
		response.on('data', function (chunk) {
            if (response.statusCode == 200) body += chunk;
        });
    });
}