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G.723.1
G.723.1 is an audio codec for voice that compresses voice audio in frames. An algorithmic look-ahead of duration means that total algorithmic delay is . Its official name is ''Dual rate speech coder for multimedia communications transmitting at 5.3 and ''. It is sometimes associated with a Truespeech trademark in coprocessors produced by DSP Group. This is a completely different codec from G.723. There are two bit rates at which G.723.1 can operate: * (using 24-byte frames) using a MPC-MLQ algorithm (MOS 3.9) * (using 20-byte frames) using an ACELP algorithm (MOS 3.62) Use G.723.1 is mostly used in Voice over IP (VoIP) applications due to its low bandwidth requirement. Music or tones such as DTMF or fax tones cannot be transported reliably with this codec, and thus some other method such as G.711 or out-of-band methods should be used to transport these signals. The complexity of the algorithm is below 16 MIPS. 2.2 kilobytes of RAM is needed for codebooks. G.723.1 is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comparison Of Audio Coding Formats
The following tables compare general and technical information for a variety of audio coding formats. For listening tests comparing the perceived audio quality of audio formats and codecs, see the article Codec listening test. General information Notes # The 'Music' category is merely a guideline on commercialized uses of a particular format, not a technical assessment of its capabilities. (For example, in terms of marketshare, MP3 and AAC dominate the personal audio market, though many other formats are comparably well suited to fill this role from a purely technical standpoint.) # First public release date is first of either specification publishing or source releasing, or in the case of closed-specification, closed-source codecs, is the date of first binary releasing. Many developing codecs have pre-releases consisting of pre-1.0 versions and perhaps 1.0 release candidates (RCs), although 1.0 may not necessarily be the release version. # Latest stable version is that of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Truespeech
Truespeech is a proprietary audio codec produced by the DSP Group. It is designed for encoding voice data at low bitrates (8.5kbps for 8kHz samples), and to be embedded into DSP chips. Truespeech had been integrated into Windows Media Player in older versions of Windows, but no longer supported since Windows Vista. It was also the format used by the voice chat features of Yahoo! Messenger. It is implemented through the ''Tsd32.dll'' A Truespeech decoder was implemented in the 0.5 release of FFmpeg FFmpeg is a free and open-source software project consisting of a suite of libraries and programs for handling video, audio, and other multimedia files and streams. At its core is the command-line ffmpeg tool itself, designed for processing of vid .... References {{Reflist Audio codecs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ACELP
Algebraic code-excited linear prediction (ACELP) is a speech coding algorithm in which a limited set of pulses is distributed as excitation to a linear prediction filter. It is a linear predictive coding (LPC) algorithm that is based on the code-excited linear prediction (CELP) method and has an algebraic structure. ACELP was developed in 1989 by the researchers at the Université de Sherbrooke in Canada. The ACELP method is widely employed in current speech coding standards such as AMR, EFR, AMR-WB (G.722.2), VMR-WB, EVRC, EVRC-B, SMV, TETRA, PCS 1900, MPEG-4 CELP and ITU-T G-series standards G.729, G.729.1 (first coding stage) and G.723.1. The ACELP algorithm is also used in the proprietary ACELP.net codec. Audible Inc. use a modified version for their speaking books. It is also used in conference-calling software, speech compression tools and has become one of the 3GPP formats. The ACELP patent expired in 2018 and is now royalty-free. Features The main advantage of ACE ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RTP Audio Video Profile
The Real-time Transport Protocol (RTP) specifies a general-purpose data format and network protocol for transmitting digital media streams on Internet Protocol (IP) networks. The details of media encoding, such as signal sampling rate, frame size and timing, are specified in an RTP payload format. The format parameters of the RTP payload are typically communicated between transmission endpoints with the Session Description Protocol (SDP), but other protocols, such as the Extensible Messaging and Presence Protocol (XMPP) may be used. Audio and video payload types RFC 3551, entitled RTP Profile for Audio and Video (RTP/AVP), specifies the technical parameters of payload formats for audio and video streams. The standard also describes the process of registering new payload types with IANA; additional payload formats and payload types are defined in the following specifications: * , Standard 65, ''RTP Profile for Audio and Video Conferences with Minimal Control'' * , ''Media Type Regis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Codecs
The following is a list of compression formats and related codecs. Audio compression formats Non-compression * Linear pulse-code modulation (LPCM, generally only described as PCM) is the format for uncompressed audio in media files and it is also the standard for CD-DA; note that in computers, LPCM is usually stored in container formats such as WAV, AIFF, or AU, or as raw audio format, although not technically necessary. ** FFmpeg * Pulse-density modulation (PDM) ** Direct Stream Digital (DSD) is standard for Super Audio CD *** foobar2000 Super Audio CD Decoder (based on MPEG-4 DST reference decoder) *** FFmpeg (based on dsd2pcm) * Pulse-amplitude modulation (PAM) Lossless compression * Actively used ** Most popular *** Free Lossless Audio Codec (FLAC) **** libFLAC **** FFmpeg *** Apple Lossless Audio Codec (ALAC) **** Apple QuickTime **** libalac **** FFmpeg **** Apple Music *** Monkey's Audio (APE) **** Monkey's Audio SDK **** FFmpeg (decoder only) *** OptimFROG (OFR) *** T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3G-324M
3G-324M is the 3GPP umbrella protocol for video telephony in 3G mobile networks. The 3G-324M protocol operates over an established circuit switched connection between two communicating peers. 3G-324M is an umbrella specification to enable conversational multimedia communication over Circuit Switched (CS) networks and has been adopted by the 3GPP. 3G-324M is based on the ITU-T H.324 specification for multimedia conferencing over Circuit switched networks.IMTC Press Coverage , International Multimedia Telecommunications Consortium (IMTC), April 1, 2001 to November 16, 2004.Orr, Eli News & Analysis: Understanding The 3G-324M Spec EETimes.com website. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Université De Sherbrooke
The University of Sherbrooke ( French: Université de Sherbrooke) (UdS) is a large public French-language university in Quebec, Canada with campuses located in Sherbrooke and Longueuil, a suburb of Montreal approximately west of Sherbrooke. It is one of two universities in the Estrie region of Quebec (the other one being Bishop's University), and the only French-language university for the region. As of 2022, the Université de Sherbrooke is home to 31,000 students, and an additional 3,000 older learners (age 50+) in continuing education in its "University of the Third Age". Of its 7,400 employees, about 4,000 are teaching staff. The university has over 100,000 graduates and offers 46 undergraduate, 48 master's and 27 doctoral programs. It holds a total of 61 research chairs, among which are the pharmacology, microelectronics, statistical learning, and environment research chairs. Campus The Université de Sherbrooke has five campuses: * The Main Sherbrooke Campus * The Sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patent Pool
In patent law, a patent pool is a consortium of at least two companies agreeing to cross-license patents relating to a particular technology. The creation of a patent pool can save patentees and licensees time and money, and, in case of blocking patents, it may also be the only reasonable method for making the invention available to the public. Competition law issues are usually important when a large consortium is formed. History In 1856, sewing machine manufacturers Grover & Baker, Singer, and Wheeler & Wilson, all accusing each other of patent infringement, met in Albany, New York to pursue their suits. Orlando B. Potter, a lawyer and president of Grover & Baker, proposed that, rather than squander their profits on litigation, they pool their patents. This was the first patent pool, a process which enables the production of complicated machines without legal battles over patent rights. In 1917, the two major patent holders for airplanes, the Wright Company and the Curtiss Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AudioCodes
AudioCodes Ltd. is a provider of advanced communications software, products and productivity solutions. Its services enable enterprises and service providers to build and operate all-IP voice networks for unified communications (UC), contact centers and hosted business services. Founded in 1993 by Shabtai Adlersberg and Leon Bialik, AudioCodes is listed on the NASDAQ stock exchange (NASDAQ: AUDC) and the Tel Aviv Stock Exchange. AudioCodes' international headquarters and R&D facilities are located in Israel, with international branch offices. More than 60 of the world's top 100 service providers use AudioCodes technology, including AT&T, Verizon, BT, DT and Telefónica. Solutions AudioCodes supplies suites of solutions for the enterprise and service provider markets. These include One Voice for Microsoft 365 to accelerate the voice-enablement of Microsoft Teams. Products AudioCodes’ product portfolio includes: * The Mediant family of multi-service business routers (MSB ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
France Telecom
Orange S.A. (), formerly France Télécom S.A. (stylized as france telecom) is a French multinational telecommunications corporation. It has 266 million customers worldwide and employs 89,000 people in France, and 59,000 elsewhere. In 2015, the group had revenue of €40 billion. The company's head office is located in the 15th arrondissement of Paris. Orange has been the company's main brand for mobile, landline, internet and Internet Protocol television (IPTV) services since 2006. The Orange brand originated in the United Kingdom in 1994 after Hutchison Whampoa acquired a controlling stake in Microtel Communications: that company became a subsidiary of Mannesmann in 1999 and then was acquired by France Télécom in 2000. The France Télécom company was rebranded to Orange on 1 July 2013. The company has faced criticism due to the Orange S.A. suicides. History Nationalised service (1878–1980s) In 1792, under the French Revolution, the first communication n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ITU-T
The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunications and Information Communication Technology such as X.509 for cybersecurity, Y.3172 and Y.3173 for machine learning, and H.264/MPEG-4 AVC for video compression, between its Member States, Private Sector Members, and Academia Members. The first meeting of the World Telecommunication Standardization Assembly (WTSA), the sector's governing conference, took place on 1 March of that year. ITU-T has a permanent secretariat called the Telecommunication Standardization Bureau (TSB), which is based at the ITU headquarters in Geneva, Switzerland. The current director of the TSB is Chaesub Lee (of South Korea), whose first 4-year term commenced on 1 January 2015, and whose second 4-year term commenced on 1 January 2019. Chaesub Lee succeeded Malcolm Johnson (Director), Malc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nippon Telegraph And Telephone Corporation
, commonly known as NTT, is a Japanese telecommunications company headquartered in Tokyo, Japan. Ranked 55th in ''Fortune'' Global 500, NTT is the fourth largest telecommunications company in the world in terms of revenue, as well as the third largest publicly traded company in Japan after Toyota and Sony, as of June 2022. The company is incorporated pursuant to the NTT Law (). The purpose of the company defined by the law is to own all the shares issued by Nippon Telegraph and Telephone East Corporation (NTT East) and Nippon Telegraph and Telephone West Corporation (NTT West) and to ensure proper and stable provision of telecommunications services all over Japan including remote rural areas by these companies as well as to conduct research relating to the telecommunications technologies that will form the foundation for telecommunications. On 1 July 2019, NTT Corporation launched NTT Ltd., an $11 billion de facto holding company business consisting of 28 brands from across NTT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
