var base64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
var base64DecodeChars = new Array(
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
	52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
	-1,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,
	15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
	-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
	41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1);

function base64encode(str) {
	var out, i, len;
	var c1, c2, c3;

	len = str.length;
	i = 0;
	out = "";
	while (i < len) {
		c1 = str.charCodeAt(i++) & 0xff;
		if (i == len) {
			out += base64EncodeChars.charAt(c1 >> 2);
			out += base64EncodeChars.charAt((c1 & 0x3) << 4);
			out += "==";
			break;
		}
		c2 = str.charCodeAt(i++);
		if (i == len) {
			out += base64EncodeChars.charAt(c1 >> 2);
			out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));
			out += base64EncodeChars.charAt((c2 & 0xF) << 2);
			out += "=";
			break;
		}
		c3 = str.charCodeAt(i++);
		out += base64EncodeChars.charAt(c1 >> 2);
		out += base64EncodeChars.charAt(((c1 & 0x3) << 4) | ((c2 & 0xF0) >> 4));
		out += base64EncodeChars.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >> 6));
		out += base64EncodeChars.charAt(c3 & 0x3F);
	}
	return out;
}

function base64decode(str) {
	var c1, c2, c3, c4;
	var i, len, out;

	len = str.length;
	i = 0;
	out = "";
	while (i < len) {

		do {
			c1 = base64DecodeChars[str.charCodeAt(i++) & 0xff];
		} while (i < len && c1 == -1);
		if (c1 == -1) break;

		do {
			c2 = base64DecodeChars[str.charCodeAt(i++) & 0xff];
		} while (i < len && c2 == -1);
		if (c2 == -1) break;

		out += String.fromCharCode((c1 << 2) | ((c2 & 0x30) >> 4));

		do {
			c3 = str.charCodeAt(i++) & 0xff;
			if (c3 == 61) return out;
			c3 = base64DecodeChars[c3];
		} while (i < len && c3 == -1);
		if (c3 == -1) break;

		out += String.fromCharCode(((c2 & 0XF) << 4) | ((c3 & 0x3C) >> 2));

		do {
			c4 = str.charCodeAt(i++) & 0xff;
			if (c4 == 61) return out;
			c4 = base64DecodeChars[c4];
		} while (i < len && c4 == -1);
		if (c4 == -1) break;
		out += String.fromCharCode(((c3 & 0x03) << 6) | c4);
	}
	return out;
}