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TRUESPEECH 6.3/5.3= I T U/T G.723.1
ITU G.723.1 Speech Compression Technology for the ITU H.324 and H.323 Videconferencing/Telephony Standards
G.723.1(Originally called TrueSpeech 6.3/5.3) is a member in the TrueSpeech Family of high quality, low bit rate, speech compression algorithms from DSP Group, Inc., it produces digital voice compression levels of 20:1 and 24:1 (6.3 Kbps and 5.3 Kbps). After an extensive series of quality tests and evaluations of various coders, the International Telecommunications Union (ITU) selected TrueSpeech 6.3/5.3 Kbps (G.723.1) as the voice compression standard for the H.324 videoconferencing standard. H.324 standardizes videoconferencing/telephony over public telephone networks, such as the Internet. G.723.1 is also recommended as the low bit rate speech technology for the ITU H.323 audio and video standard which is supported by Microsoft, Intel and hundreds of other companies as the standard for communications on the Internet
This algorithm is applicable for real-time video and teleconferencing applications where reduced bandwidth and very high quality voice is required. Thus, this technology is ideal for Internet video, VOIP (Voice Over Internet Protocol) applications, audio, videoconferencing, VOD (Video On Demand) applications and Internet telephony applications which enables interoperability between telephony applications both on, and off, the Net.
DSP Group offers Integrated Digital Telephony Processors based on TrueSpeech. DSP Group also licenses a G.723.1 algorithm for videoconferencing, computer telephony, Internet, and numerous other multimedia applications.
Quality
A quality test called Mean Opinion Score (MOS) is used to rate the quality of different speech CODECs. On this scale, a score of 4.0 is considered "toll" quality, the quality of speech heard through a normal telephone line. In tests performed by Dynastat, TrueSpeech G.723.1 received a rating of 3.98 - only 2 hundredths of a point away from full toll quality! Thus, TrueSpeech G.723.1 can enable voice communications through the Internet as well as in other applications requiring compression with voice quality equal to that experienced over a regular telephone.
TrueSpeech was selected by the ITU as the G.723.1 standard only after extensive testing. TrueSpeech G.723.1 was tested under a variety of conditions including situations with background noise, individuals speaking different languages, male and female talkers, multiple people talking simultaneously, etc. The coder was also tested to determine its robustness to handling lost packets, also called frame erasure. The ability to handle lost packets is especially important to enabling high quality voice communications in the Internet environment. TrueSpeech G.723 outperformed offerings from a number of industry leading companies under these strict testing environments to be selected by the ITU as the G.723.1 coder.
TrueSpeech G.723.1 with Voice Activity Detection (VAD) and Comfort Noise Generation (CNG) compresses speech down up to an additional 25-30% below the 6.3 Kbps and 5.3 Kbps rate. The VAD code compresses out the silent portions between words and sentences and provides an effective compression rate of up to 3.7 Kbps (35:1). The amount of additional compression provided by VAD will vary and depends on the actual speech content.
For licensing information please contact our TrueSpeech licensing manager at TrueSpeech@dsp.co.il
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G.723.1/A Licensing
Consortium Members
