protected Void doInBackground() throws Exception {
fireWorkerStart();
try {
final CryptoSymmetricAlgo algo = (CryptoSymmetricAlgo) cbCodecs.getSelectedItem();
final CryptoSymmetric crypto = new CryptoSymmetricImpl(algo);
final SecretKey key = crypto.generateKey(new String(password.getPassword())
.getBytes(Constants.ENCODING_DEFAULT));
crypto.decrypt(scrambler.getModuleData().getFile(KEY_UNSCRAMBLE_INPUT), scrambler.getModuleData()
.getFile(KEY_UNSCRAMBLE_OUTPUT), key);