For instance Just Talk Inc. , an Ann Arbor speech recognition company, has developed software that allows businesspeople on the go to update their computer calendars, contact lists and even their sales inventories with a phone call. While the system can't understand conversation, it picks up particular words from a caller's sentence. Commands essentially limit the field of words a system has to recognize helping to increase the rate at which computers can accurately understand speech. Much of today's software can reach up to 90-percent accuracy, even higher with training, experts say. But strong accents, high-pitched voices and speech impediments can throw accuracy rates off.
Background noise can also confuse voice-recognition systems.
Unlike people, computers cannot focus on a particular speaker and drown out the rest of the background noise, explains Raymond Gunn, CEO of Clarity, a Troy company that makes software that enables computers to separate a speaker's voice from other noise. Gunn said Clarity's software can boost a system's accuracy rate from 90 percent up to as high as 97 percent. Background noise is a particularly big issue in cars and public places where people use cell phones. People at homes and offices can always type on a PC, but people who are driving or walking through an airport can't open a laptop. They could speak into a speaker phone or cell phone.