Fast and Robust Recognition of Aztec Codes Aztec code reading reading licenses include pylon vTools for recognizing and decoding Aztec codes. Easy to implement, they provide the fastest path to powerful Aztec code recognition with best-in-class recognition rates.pylon vTools are part of Basler's pylon Software Suite. Licenses for pylon vTools can be protected by hardware dongles. If you want to run multiple systems with pylon vTools at the same time, you will need one dongle for each system.