22-04-2010, 12:35 AM
Introduction
In telephony, interactive voice response, or IVR, is a computerized system that allows a person, typically a telephone caller, to select an option from a voice menu and otherwise interface with a computer system. Generally the system plays pre-recorded voice prompts to which the person presses a number on a telephone keypad to select the option chosen, or speaks simple answers such as "yes", "no", or numbers in answer to the voice prompts.
The latest systems use natural language speech recognition to interpret the questions that the person wants answered.
Other innovations include the ability to speak complex and dynamic information such as an e-mail, news report or weather information using Text-To-Speech (TTS). TTS is computer generated synthesised speech and is no longer the robotic voice people associate with computers. Real voices are used to create the speech in tiny fragments that are glued together before being played to the caller.
IVR systems can be used to create and manage many services including telephone banking, order placement, caller identification and routing, balance inquiry, and airline ticket booking. Voicemail systems are different from IVR systems in that they are a one-way communication tool (the caller leaves a message), whereas IVR systems attempt two-way interaction with the caller. Automatic call distributor (ACD) systems are often the first point of contact when calling many larger businesses, and can be used in place of more expensive IVR systems. IVR systems are generally used at the front end of call centers to identify what service the caller wants and to extract numeric information such as account numbers as well as provide answers to simple questions such as account balances or allow pre-recorded information to be heard.
Implementation
With simple voice modem any one can develop an IVR System. Windows TAPI (Telephonic Application Programming Interface) Provides many library function to handle the call. For details browse MSDN site. This API can be integrated to any visual studio language (VB 6, VC 6 and .NET). While playing voice over the device make sure that you have converted the audio file (*.wav only) to telephone quality. (8KB/S mono).
