Method and system including fingerprint and image scanning for authentication

A computer system and method having an energy-efficient multi-biometric authentication that includes a fingerprint scanner, a camera, a memory, and a processing circuitry. The processing circuitry reads a predefined probability from the memory and generates a random number. The processing circuitry inputs a user ID and retrieves a trust value for the user from a trust database. The processing circuitry obtains a scanned user fingerprint using a fingerprint scanner and obtains a captured user face using the camera. The processing circuitry applies a reward to the trust value to increase the trust value when the scanned user fingerprint is substantially the same as the stored user fingerprint and the captured user face is substantially the same as a stored user face in a face database, store the trust value as the cumulative trust value for the user, and authenticate the user to allow access to the computer system.