1. Real-Time Text:
Real-time text is text transmitted instantly while it is being typed or created. The recipient can immediately read the sender’s text as it is written, without waiting. It combines the advantages of text-based messaging, with the interactive conversational nature of a telephone conversation. Source: http://www.realtimetext.org/standard-graphics
2. Real-Time Captions:
Captions, composed of text, are used by people who are deaf or hard of hearing to access content delivered by spoken words and sounds. Real-time captions, or Computer Assisted Real-time Translation (CART), are created as an event takes place. In this instance, text is being streamed in real-time, one-word/phrase-at-a-time. A captioner (often trained as a court reporter or stenographer) uses a stenotype machine with a phonetic keyboard and special software. A computer translates the phonetic symbols into captions almost instantaneously and displays them on a laptop or on a large display screen. A slight delay may occur because of the captioner’s need to hear and enter the words and the computer’s processing time. Real-time captioning can be used for programs that do not have written scripts or captions such as: lectures, classes, congressional or council meetings, news programs, and non-broadcast meetings, such as those of professional associations.
Remote real-time captions are produced at a remote location and then transmitted to the site where the program is taking place. For example, in a lecture hall an instructor can talk into a microphone that is connected via telephone lines to a captioner in a different city. From that location, the captioner, using similar equipment as described above, transmits the captioned text via the internet, using special software, to a laptop in the lecture hall- or to a laptop in a student’s home, if they are unable to attend the lecture in person. Although most real-time captioning has been estimated to be well over ninety percent accurate, the audience will see occasional errors. The captioner may misunderstand a word, hear an unfamiliar word, or there may be an error in the software dictionary.
Captions can also benefit individuals who understand the written better than the spoken word of the language in which a presentation is delivered as well as people who are viewing the program in a noisy (e.g., airport or sports bar) or noiseless (e.g., a work cubicle) environment. Captions that are not “real-time” include those provided on television programming and those made available on prerecorded video that can be rented or purchased. Source: http://www.washington.edu/doit/what-real-time-captioning
3. Real-Time Automatic Speech to Text (Automated Speech Recognition):
Real-Time Automatic Speech to Text can be defined as the independent, computer‐driven transcription of spoken language into readable text in real time. It is technology that allows a computer to identify the words that a person speaks into a microphone or telephone and immediately convert it into written text. Although ASR technology is not yet at the point where machines understand all speech, in any acoustic environment, or by any person, it is used on a day‐to‐day basis in a number of applications and services. The ultimate goal of ASR research is to allow a computer to recognize in real‐time, with 100% accuracy, all words that are intelligibly spoken by any person, independent of vocabulary size, noise, speaker characteristics or accent. Source: http://support.docsoft.com/help/whitepaper-asr.pdf
4. Real-Time Captioning Using Speech Recognition:
In this instance, speech recognition technology is used to generate real-time captions. See definition for “Real-Time Captions,” above.
5. Speech2RTT® Communications:
Speech2RTT® communications uses the same technology as real-time captioning using speech recognition. However, the technology is optimized and adapted to implementing it as a two-way mobile communications service that enables two individuals to conduct a real-time text conversation using their voices (or standard/Braille keyboard). In this instance, text is being streamed in real-time, one-word at a time.