21 June 2000 Speech recognition technology has improved tremendously over the last three years. The difference lies in the computing power available. The tremendous power of PCs today lets speech recognition software tear through huge databases of sound libraries to find the best word match. Better computing power also makes it possible to implement smarter artificial intelligence that understands the context of the sentence.
Developers start by first making voice recordings of people reading a variety of text.
The recordings are then converted into digital signals. To reduce storage space, signals that lie outside the sensitive bandwidth of human hearing between 5 KHz to 50KHz are removed. At the same time, the developer creates digital notes that are associated with pronunciation of phrases. These are called phonetic notes. Just as musical notes describe a tune when pieced together, phonetic notes form a phrase or sentence when strung together.