function base64encode(str) {

	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);
	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;
}