1function _base64ToArrayBuffer(base64) {
2 var binary_string = window.atob(base64);
3 var len = binary_string.length;
4 var bytes = new Uint8Array(len);
5 for (var i = 0; i < len; i++) {
6 bytes[i] = binary_string.charCodeAt(i);
7 }
8 return bytes.buffer;
9}