Telepresence, which integrates life-size High Definition (HD) video with high-quality sound in a room setup, creates the feel of actually being in the same room as participants at other locations. The technology can be implemented anywhere in the world utilizing the global Internet Protocol (IP) network, as simple as walking into the conference room next door. Establishing a virtual meeting place, however, isn’t the only application of telepresence technology. With its high definition cameras and huge projection screens, systems are also able to illustrate physical characteristics and cues, such as a sweaty brow, in great detail. Communication is mostly non-verbal than verbal and this renders telepresence an ideal vehicle for business negotiations and sales pitches. Then there is telepresence’s potential for allowing human resource executives to interview job candidates from afar while still getting a feeling for an applicant’s personality. The technology is also employed in other sectors such as education, health, military and government. In the not-so-far future, it’s likely that telepresence will aid geographically scattered engineers and product managers in the product development process.
In technical terms telepresence is similar to video conferencing, only that it gives an immersive experience. It provides stimuli such that the user perceives no differences from actual presence of the counterpart. As the screen size increases, so does the sense of immersion, as well as the range of subjective mental experiences available to viewers. The stimuli depends on the application and bandwidth used. Consider a person watching television, for example, the primary senses of vision and hearing are stimulated giving the impression that the watcher is no longer at home. Similar capabilities give telepresence a level of visual and acoustic realism that encourages active usage. The quality of experience also may be influenced by room customization. While high-end telepresence users might have many of these added services, other users may have simple rooms outfitted with plug-and- play, high definition technology. Indeed, any room can be a telepresence room.
The fundamental methodology used in a telepresence system is digital compression of audio and video streams in real time. The audio and video signal is sampled and quantized, a process called encoding. This process results in a digital stream of 1s and 0s is subdivided into labeled packets, which are then transmitted over the global IP network. The receiving telepresence system decodes the digital stream to display the visual and generate the audio. The hardware or software that performs this compression is called a codec (coder/decoder). To create a vivid, compelling and natural experience a resolution of between 720p and 1080p at 30 frames per second is deployed, giving a crystal clear video stream. For audio standards-based wideband codecs are implemented to improve the voice quality carried over IP networks. Wideband codecs provide clearer, more lifelike voice communications and markedly improved intelligibility because of the additional voice data included in the audio stream. They also double the voice signal range, in the range of 30 hertz to 7000 hertz or higher, while using the same network bandwidth as narrowband codecs.
