• Quick prototyping and development of new products and services The technology must support the creation of new products and services based on speech in an efficient and timely fashion.
In this paper I present a vision of the voice-processing industry with a focus on the areas with the broadest base of user penetration: speech recognition, text-to-speech synthesis, natural language processing, and speaker recognition technologies. The current and future applications of these technologies in the telecommunications industry will be examined in terms of their strengths, limitations, and the degree to which user needs have been or have yet to be met. Although noteworthy gains have been made in areas with potentially small user bases and in the more mature speech-coding technologies, these subjects are outside the scope of this paper.
As the telecommunications industry evolves over the next decade to provide the products and services that people will desire, several key technologies will become commonplace. Two of these, automatic speech recognition (ASR) and text-to-speech synthesis (TTS), will provide users with more freedom regarding when, where, and how they can access information. Although these technologies are currently in their infancy, their capabilities are increasing rapidly and their use in today's telephone network is expanding.
Beginning with advances in speech coding, which now allows for high-speed transmission of audio signals, speech-processing technologies and telecommunications are the perfect marriage of a technology and an industry. Currently, the voice-processing market is projected to be over $1.5 billion by 1994 and is growing at about 30 percent a per year (Meisel; Oberteuffer; The Yankee Group, 1991). Figure 1 shows a plot of the projected growth of voice-processing equipment sales from 1989 to 1993. The two driving forces behind this growth are (1) the increased demand for interactive voice services such as voice response and voice messaging and (2) the rapid improvement in speech recognition and synthesis technologies.
Figures 2 and 3 shows the current (as of December 1991) distribution of market share for the voice-messaging and voice response markets, respectively. These figures show Octel being the market leader for voice-messaging systems and AT&T the market leader in voice response systems. The data also indicate that there is no one dominant system provider in either product family. These data obviously represent a maturing industry and a mature technology (speech cod-