code: public final static void getBlowfishSignature(byte[] array, int offset, int keyid) {
          BlowfishEngine bf = new BlowfishEngine();
          // need to use little endian
          bf.init(true, new KeyParameter(BLOWFISH_KEYS[keyid]));
          byte[] output = new byte[8];
          bf.processBlock(array, offset, output, 0);
          System.arraycopy(output, 0, array, offset, 8);
      }
docs: RTMPE type 9 uses Blowfish on the regular signature http://en.wikipedia.org/wiki/Blowfish_(cipher)
  
  @param array array to get signature
  @param offset offset to start from
  @param keyid ID of XTEA key