qt base64(sha1(str));

QString str=  sha1("Wc+4gwUg+DUqwyyGdHhUxg==258EAFA5-E914-47DA-95CA-C5AB0DC85B11");

qDebug()<<str;//"6cBtYqYBqGB9dIbUSSylAnGjOIE="
 
QString sha1(QString str)

{
QByteArray string = str.toLatin1();
QCryptographicHash *hash=new QCryptographicHash(QCryptographicHash::Sha1);
hash->addData(string);
QByteArray sha1=hash->result();
return sha1.toBase64();
}

QByteArray bb;

bb = QCryptographicHash::hash(str.toLatin1(), QCryptographicHash::Sha1); qDebug() << bb.toBase64();