Speech Recognition vs. Speaker Recognition

People often get confused between speech recognition and speaker recognition. Let’s explore the difference.

Simply stated, speech recognition is the ability to recognize what a person is saying. Speaker recognition on the other hand is the ability to identify the person speaking.

Speech recognition has been in use for decades. Today, many organizations have replaced live agents with automated interactive voice response (IVR) systems. The IVRs may prompt users to speak their entries. For example, when calling directory assistance, users are prompted to speak the name of the individual or business that they are inquiring about. The system converts the spoken phrases to text, recites them back to the user for verification, and searches the database for a match.

Speaker recognition is a relatively new technology. Using voice biometrics, a speaker recognition system is able to identify, or verify the identity, of a person who has previously enrolled (i.e., provided a base voiceprint) in the system. A voiceprint is a stored set of measurable characteristics of a human voice that are unique to each individual. A sample voiceprint can be compared to a base voiceprint to identify, or verify the identity, of a person. Speaker recognition is an ideal way to verify the identity of a person remotely (e.g., performing a financial transaction via telephone).

Early History of Voice Biometrics

Most people think of voice biometrics as a relatively new technology. However, according to a 2004 article by Lisa Myers (SANS Institute), the history of voice biometrics actually began in 1867. At that time, Alexander Graham Bell’s father began work on developing an early voiceprint. Jumping ahead to World War 2, the same article mentions the pioneering work by Bell Telephone Labs on spectrograms. The concept was to identify a specific enemy’s voice and track their movements by the location of their radio transmissions. Apparently, the technology did not work very well.

Fast forward two decades. According to the National Science and Technology Council, in 1960, a Swedish professor, Gunnar Fant, published a ground-breaking model describing the physiological components of acoustic speech production. Fant’s model was expanded in 1970, by Dr. Joseph Perkell, to include the tongue and jaw. In 1976, Texas Instruments developed a prototype voice biometrics system that was tested by the United States Air Force and Mitre Corporation. Voice biometrics was on its way!