Base64 encode http://jsperf.com/base64-encode/3 ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/ and =

Base64novnc.js

var Base64novnc = {
    encode: function(data) {
        "use strict";
        var result = '';
        var toBase64Table = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/='.split('');
        var length = data.length;
        var lengthpad = (length % 3);
        // Convert every three bytes to 4 ascii characters.
        for (var i = 0; i < (length - 2); i += 3) {
            result += toBase64Table[data[i] >> 2];
            result += toBase64Table[((data[i] & 0x03) << 4) + (data[i + 1] >> 4)];
            result += toBase64Table[((data[i + 1] & 0x0f) << 2) + (data[i + 2] >> 6)];
            result += toBase64Table[data[i + 2] & 0x3f];
        }
        // Convert the remaining 1 or 2 bytes, pad out to 4 characters.
        var j = 0;
        if (lengthpad === 2) {
            j = length - lengthpad;
            result += toBase64Table[data[j] >> 2];
            result += toBase64Table[((data[j] & 0x03) << 4) + (data[j + 1] >> 4)];
            result += toBase64Table[(data[j + 1] & 0x0f) << 2];
            result += toBase64Table[64];
        } else if (lengthpad === 1) {
            j = length - lengthpad;
            result += toBase64Table[data[j] >> 2];
            result += toBase64Table[(data[j] & 0x03) << 4];
            result += toBase64Table[64];
            result += toBase64Table[64];
        }
        return result;
    }
};