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51-561: MPEG-1 Audio Layer 2 encoding was derived from the MUSICAM ( Masking pattern adapted Universal Subband Integrated Coding And Multiplexing ) audio codec, developed by Centre commun d'études de télévision et télécommunications (CCETT), Philips , and the Institut für Rundfunktechnik (IRT) in 1989 as part of the EUREKA 147 pan-European inter-governmental research and development initiative for

102-476: A broadcasting system using COFDM modulation was demonstrated on air and on the field together with Radio Canada and CRC Canada during the NAB show (Las Vegas) in 1991. The implementation of the audio part of this broadcasting system was based on a two chips encoder (one for the subband transform, one for the psychoacoustic model designed by the team of G. Stoll (IRT Germany), later known as Psychoacoustic model I in

153-519: A compatible soundcard rather than the system CPU. MPEG-1 Audio Layer II is the audio format used in Digital Audio Broadcast (DAB), a digital radio standard for broadcasting digital audio radio services in many countries around the world. The BBC Research & Development department states that at least 192 kbit/s is necessary for a high fidelity stereo broadcast: A value of 256 kbit/s has been judged to provide

204-555: A digital audio two-channel compression system known as Musicam or MPEG Audio Layer II. MPEG-1 Audio Layer II is defined in ISO/IEC 11172-3 (MPEG-1 Part 3) An extension has been provided in MPEG-2 Audio Layer II and is defined in ISO/IEC 13818-3 (MPEG-2 Part 3) The format is based on successive digital frames of 1152 sampling intervals with four possible formats: MPEG audio may have variable bit rate (VBR), but it

255-542: A document is submitted directly for approval as a draft International Standard (DIS) to the ISO member bodies or as a final draft International Standard (FDIS), if the document was developed by an international standardizing body recognized by the ISO Council. The first step, a proposal of work (New Proposal), is approved at the relevant subcommittee or technical committee (e.g., SC 29 and JTC 1 respectively in

306-401: A high quality stereo broadcast signal. However, a small reduction, to 224 kbit/s is often adequate, and in some cases it may be possible to accept a further reduction to 192 kbit/s, especially if redundancy in the stereo signal is exploited by a process of 'joint stereo' encoding (i.e. some sounds appearing at the centre of the stereo image need not be sent twice). At 192 kbit/s, it

357-442: A long process that commonly starts with the proposal of new work within a committee. Some abbreviations used for marking a standard with its status are: Abbreviations used for amendments are: Other abbreviations are: International Standards are developed by ISO technical committees (TC) and subcommittees (SC) by a process with six steps: The TC/SC may set up working groups  (WG) of experts for

408-455: A mostly backward compatible extension which adds support for multichannel audio , variable bit rate encoding, and additional sampling rates, defined in ISO/IEC 13818-3. The abbreviation MP2 is also sometimes erroneously applied to MPEG-2 video or MPEG-2 AAC audio. Centre commun d%27%C3%A9tudes de t%C3%A9l%C3%A9vision et t%C3%A9l%C3%A9communications CCETT or Centre commun d'études de télévision et télécommunications ( Centre for

459-427: A part of the EUREKA research program. The Eureka 147 System comprised three main elements: MUSICAM Audio Coding ( Masking pattern Universal Sub-band Integrated Coding And Multiplexing ), Transmission Coding & Multiplexing and COFDM Modulation. MUSICAM was one of the few codecs able to achieve high audio quality at bit rates in the range of 64 to 192 kbit/s per monophonic channel. It has been designed to meet

510-548: A proposal to form a new global standards body. In October 1946, ISA and UNSCC delegates from 25 countries met in London and agreed to join forces to create the International Organization for Standardization. The organization officially began operations on 23 February 1947. ISO Standards were originally known as ISO Recommendations ( ISO/R ), e.g., " ISO 1 " was issued in 1951 as "ISO/R 1". ISO

561-436: A relatively small number of standards, ISO standards are not available free of charge, but rather for a purchase fee, which has been seen by some as unaffordable for small open-source projects. The process of developing standards within ISO was criticized around 2007 as being too difficult for timely completion of large and complex standards, and some members were failing to respond to ballots, causing problems in completing

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612-413: A result, Windows Media Player will directly play Content Depot files, however, less intelligent .wav players often do not. As the encoding and decoding process would have been a significant drain on CPU resources in the first generations of broadcast playout systems, professional broadcast playout systems typically implement the codec in hardware, such as by delegating the task of encoding and decoding to

663-555: A wide range of applications in digital radio and TV broadcasting (later DAB , DMB , DVB ), and use on CD-ROM (later Video CD ). The MUSICAM audio coding was one of 14 proposals for MPEG-1 Audio standard that were submitted to ISO in 1989. The MPEG-1 Audio standard was based on the existing MUSICAM and ASPEC audio formats. The MPEG-1 Audio standard included the three audio "layers" (encoding techniques) now known as Layer I (MP1), Layer II (MP2) and Layer III (MP3). All algorithms for MPEG-1 Audio Layer I, II and III were approved in 1991 as

714-637: Is "to develop worldwide Information and Communication Technology (ICT) standards for business and consumer applications." There was previously also a JTC 2 that was created in 2009 for a joint project to establish common terminology for "standardization in the field of energy efficiency and renewable energy sources". It was later disbanded. As of 2022 , there are 167 national members representing ISO in their country, with each country having only one member. ISO has three membership categories, Participating members are called "P" members, as opposed to observing members, who are called "O" members. ISO

765-466: Is a voluntary organization whose members are recognized authorities on standards, each one representing one country. Members meet annually at a General Assembly to discuss the strategic objectives of ISO. The organization is coordinated by a central secretariat based in Geneva . A council with a rotating membership of 20 member bodies provides guidance and governance, including setting the annual budget of

816-464: Is abused, ISO should halt the process... ISO is an engineering old boys club and these things are boring so you have to have a lot of passion ... then suddenly you have an investment of a lot of money and lobbying and you get artificial results. The process is not set up to deal with intensive corporate lobbying and so you end up with something being a standard that is not clear. International Workshop Agreements (IWAs) are documents that establish

867-517: Is an abbreviation for "International Standardization Organization" or a similar title in another language, the letters do not officially represent an acronym or initialism . The organization provides this explanation of the name: Because 'International Organization for Standardization' would have different acronyms in different languages (IOS in English, OIN in French), our founders decided to give it

918-521: Is approved as an International Standard (IS) if a two-thirds majority of the P-members of the TC/SC is in favour and not more than one-quarter of the total number of votes cast are negative. After approval, the document is published by the ISO central secretariat , with only minor editorial changes introduced in the publication process before the publication as an International Standard. Except for

969-480: Is commonly used within the broadcast industry for distributing live audio over satellite, ISDN and IP Network connections as well as for storage of audio in digital playout systems. An example is NPR 's PRSS Content Depot programming distribution system. The Content Depot distributes MPEG-1 L2 audio in a Broadcast Wave File wrapper. MPEG2 with RIFF headers (used in .wav ) is specified in the RIFF/WAV standards. As

1020-522: Is funded by a combination of: International standards are the main products of ISO. It also publishes technical reports, technical specifications, publicly available specifications, technical corrigenda (corrections), and guides. International standards Technical reports For example: Technical and publicly available specifications For example: Technical corrigenda ISO guides For example: ISO documents have strict copyright restrictions and ISO charges for most copies. As of 2020 ,

1071-495: Is not widely supported. Layer II can use a method called bit rate switching. Each frame may be created with a different bit rate. According to ISO/IEC 11172-3:1993, Section 2.4.2.3: To provide the smallest possible delay and complexity, the (MPEG audio) decoder is not required to support a continuously variable bit rate when in layer I or II. Part of the DAB digital radio and DVB digital television standards. MPEG-1 Audio Layer II

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1122-425: Is produced, for example, for audio and video coding standards is called a verification model (VM) (previously also called a "simulation and test model"). When a sufficient confidence in the stability of the standard under development is reached, a working draft (WD) is produced. This is in the form of a standard, but is kept internal to working group for revision. When a working draft is sufficiently mature and

1173-617: Is relatively easy to hear imperfections in critical audio material. All DVD-Video players in PAL countries contain stereo MP2 decoders, making MP2 a possible competitor to Dolby Digital in these markets. DVD-Video players in NTSC countries are not required to decode MP2 audio, although most do. While some DVD recorders store audio in MP2 and many consumer-authored DVDs use the format, commercial DVDs with MP2 soundtracks are rare. MPEG-1 Audio Layer II

1224-617: Is restricted. The organization that is known today as ISO began in 1926 as the International Federation of the National Standardizing Associations ( ISA ), which primarily focused on mechanical engineering . The ISA was suspended in 1942 during World War II but, after the war, the ISA was approached by the recently-formed United Nations Standards Coordinating Committee (UNSCC) with

1275-691: Is the standard audio format used in the Video CD and Super Video CD formats (VCD and SVCD also support variable bit rate and MPEG Multichannel as added by MPEG-2). MPEG-1 Audio Layer II is the standard audio format used in the MHP standard for set-top boxes. MPEG-1 Audio Layer II is the audio format used in HDV camcorders. MP2 files are compatible with some Portable audio players . The term MP2 and filename extension .mp2 usually refer MPEG-1 Audio Layer II data, but can also refer to MPEG-2 Audio Layer II ,

1326-492: The French Ministry of Posts and Telecommunications ) for development of new techniques for processing, transmission and distribution of audiovisual signals. CCETT became part of France Télécom R&D , the research and development division of France Télécom in 1998. This division was derived from different ancient entities, such as CNET (the research and development centre of France Telecom, created in 1944),

1377-655: The International Electrotechnical Commission . It is headquartered in Geneva , Switzerland. The three official languages of ISO are English , French , and Russian . The International Organization for Standardization in French is Organisation internationale de normalisation and in Russian, Международная организация по стандартизации ( Mezhdunarodnaya organizatsiya po standartizatsii ). Although one might think ISO

1428-626: The AES/EBU professional digital input studio standard) were the main reasons to later adopt the characteristics of MUSICAM as the basic features for an advanced digital music compression codec such as MP3. The audio coding algorithm used by the Eureka 147 Digital Audio Broadcasting (DAB) system has been subject to the standardization process within the ISO/Moving Pictures Expert Group (MPEG) in 1989–94. MUSICAM audio coding

1479-699: The CCETT, as well as other entities. Since 2007, France Telecom R&D is also known as Orange Labs , a global network of R&D entities. CCETT/France Télécom R&D contributed to various international standards, such as ISO / IEC MPEG and JPEG standards or DAB and DVB standards. CCETT, IRT and Philips developed a digital audio two-channel compression system known as Musicam or MPEG Audio Layer II ( Emmy Award in Engineering 2000). International Organization for Standardization Early research and development: Merging

1530-488: The ISO MPEG audio standard) and a real time decoder using one Motorola 56001 DSP chip running an integer arithmetics software designed by Y.F. Dehery 's team ( CCETT , France). The simplicity of the corresponding decoder together with the high audio quality of this codec using for the first time a 48 kHz sampling frequency, a 20 bits/sample input format (the highest available sampling standard in 1991, compatible with

1581-694: The ISO Statutes. ISO was founded on 23 February 1947, and (as of July 2024 ) it has published over 25,000 international standards covering almost all aspects of technology and manufacturing. It has over 800 technical committees (TCs) and subcommittees (SCs) to take care of standards development. The organization develops and publishes international standards in technical and nontechnical fields, including everything from manufactured products and technology to food safety, transport, IT, agriculture, and healthcare. More specialized topics like electrical and electronic engineering are instead handled by

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1632-560: The Study of Television broadcasting and Telecommunication or Common Study Center of Telediffusion and Telecommunication ) was a research centre created in Rennes ( France ) in 1972 jointly by the Office de Radiodiffusion Télévision Française (ORTF) (later Télédiffusion de France ) and Centre National d'Etudes des Telecommunications (CNET) (Direction Générale des Télécommunications, part of

1683-491: The case of MPEG, the Moving Picture Experts Group ). A working group (WG) of experts is typically set up by the subcommittee for the preparation of a working draft (e.g., MPEG is a collection of seven working groups as of 2023). When the scope of a new work is sufficiently clarified, some of the working groups may make an open request for proposals—known as a "call for proposals". The first document that

1734-418: The central secretariat. The technical management board is responsible for more than 250 technical committees , who develop the ISO standards. ISO has a joint technical committee (JTC) with the International Electrotechnical Commission (IEC) to develop standards relating to information technology (IT). Known as JTC 1 and entitled "Information technology", it was created in 1987 and its mission

1785-467: The coding of audio programs with more than two channels, up to 5.1 multichannel. The Layer III ( MP3 ) component uses a lossy compression algorithm that was designed to greatly reduce the amount of data required to represent an audio recording and sound like a decent reproduction of the original uncompressed audio for most listeners. CCETT (France), IRT (Germany) and Philips (The Netherlands) won an Emmy Award in Engineering 2000 for development of

1836-790: The committee draft of ISO-11172 and finalized in 1992 as part of MPEG-1 , the first standard suite by MPEG , which resulted in the international standard ISO / IEC 11172-3 (a.k.a. MPEG-1 Audio or MPEG-1 Part 3 ), published in 1993. Further work on MPEG audio was finalized in 1994 as part of the second suite of MPEG standards, MPEG-2 , more formally known as international standard ISO/IEC 13818-3 (a.k.a. MPEG-2 Part 3 or backward compatible MPEG-2 Audio or MPEG-2 Audio BC ), originally published in 1995. MPEG-2 Part 3 (ISO/IEC 13818-3) defined additional bit rates and sample rates for MPEG-1 Audio Layer I, II and III. The new sampling rates are exactly half that of those originally defined for MPEG-1 Audio. MPEG-2 Part 3 also enhanced MPEG-1's audio by allowing

1887-421: The confidence people have in the standards setting process", and alleged that ISO did not carry out its responsibility. He also said that Microsoft had intensely lobbied many countries that traditionally had not participated in ISO and stacked technical committees with Microsoft employees, solution providers, and resellers sympathetic to Office Open XML: When you have a process built on trust and when that trust

1938-604: The development of a system for the broadcasting of audio and data to fixed, portable or mobile receivers (established in 1987). It began as the Digital Audio Broadcast (DAB) project managed by Egon Meier-Engelen of the Deutsche Forschungs- und Versuchsanstalt für Luft- und Raumfahrt (later on called Deutsches Zentrum für Luft- und Raumfahrt, German Aerospace Center) in Germany. The European Community financed this project, commonly known as EU-147, from 1987 to 1994 as

1989-413: The document, the draft is then approved for submission as a Final Draft International Standard (FDIS) if a two-thirds majority of the P-members of the TC/SC are in favour and if not more than one-quarter of the total number of votes cast are negative. ISO will then hold a ballot among the national bodies where no technical changes are allowed (a yes/no final approval ballot), within a period of two months. It

2040-721: The necessary steps within the prescribed time limits. In some cases, alternative processes have been used to develop standards outside of ISO and then submit them for its approval. A more rapid "fast-track" approval procedure was used in ISO/IEC JTC 1 for the standardization of Office Open XML (OOXML, ISO/IEC 29500, approved in April 2008), and another rapid alternative "publicly available specification" (PAS) process had been used by OASIS to obtain approval of OpenDocument as an ISO/IEC standard (ISO/IEC 26300, approved in May 2006). As

2091-619: The networks and creating the Internet: Commercialization, privatization, broader access leads to the modern Internet: Examples of Internet services: The International Organization for Standardization ( ISO / ˈ aɪ s oʊ / ) is an independent, non-governmental , international standard development organization composed of representatives from the national standards organizations of member countries. Membership requirements are given in Article 3 of

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2142-492: The next stage, called the "enquiry stage". After a consensus to proceed is established, the subcommittee will produce a draft international standard (DIS), and the text is submitted to national bodies for voting and comment within a period of five months. A document in the DIS stage is available to the public for purchase and may be referred to with its ISO DIS reference number. Following consideration of any comments and revision of

2193-468: The original MUSICAM algorithm is not used anymore. The name MUSICAM is often mistakenly used when MPEG-1 Audio Layer II is meant. This can lead to some confusion, because the name MUSICAM is trademarked by different companies in different regions of the world. (Musicam is the name used for MP2 in some specifications for Astra Digital Radio as well as in the BBC's DAB documents.) The Eureka Project 147 resulted in

2244-411: The preparation of a working drafts. Subcommittees may have several working groups, which may have several Sub Groups (SG). It is possible to omit certain stages, if there is a document with a certain degree of maturity at the start of a standardization project, for example, a standard developed by another organization. ISO/IEC directives also allow the so-called "Fast-track procedure". In this procedure,

2295-511: The publication of European Standard, ETS 300 401 in 1995, for DAB which now has worldwide acceptance. The DAB standard uses the MPEG-1 Audio Layer II (ISO/IEC 11172-3) for 48 kHz sampling frequency and the MPEG-2 Audio Layer II (ISO/IEC 13818-3) for 24 kHz sampling frequency. In the late 1980s, ISO 's Moving Picture Experts Group (MPEG) started an effort to standardize digital audio and video encoding, expected to have

2346-472: The short form ISO . ISO is derived from the Greek word isos ( ίσος , meaning "equal"). Whatever the country, whatever the language, the short form of our name is always ISO . During the founding meetings of the new organization, however, the Greek word explanation was not invoked, so this meaning may be a false etymology . Both the name ISO and the ISO logo are registered trademarks and their use

2397-509: The subcommittee is satisfied that it has developed an appropriate technical document for the problem being addressed, it becomes a committee draft (CD) and is sent to the P-member national bodies of the SC for the collection of formal comments. Revisions may be made in response to the comments, and successive committee drafts may be produced and circulated until consensus is reached to proceed to

2448-679: The technical requirements of most applications (in the field of broadcasting, telecommunication and recording on digital storage media) — low delay, low complexity, error robustness, short access units, etc. As a predecessor of the MP3 format and technology, the perceptual codec MUSICAM is based on integer arithmetics 32 subbands transform, driven by a psychoacoustic model. It was primarily designed for Digital Audio Broadcasting and digital TV, and disclosed by CCETT(France) and IRT (Germany) in Atlanta during an IEEE-ICASSP conference. This codec incorporated into

2499-414: The typical cost of a copy of an ISO standard is about US$ 120 or more (and electronic copies typically have a single-user license, so they cannot be shared among groups of people). Some standards by ISO and its official U.S. representative (and, via the U.S. National Committee, the International Electrotechnical Commission ) are made freely available. A standard published by ISO/IEC is the last stage of

2550-517: Was suggested at the time by Martin Bryan, the outgoing convenor (chairman) of working group 1 (WG1) of ISO/IEC JTC 1/SC 34 , the rules of ISO were eventually tightened so that participating members that fail to respond to votes are demoted to observer status. The computer security entrepreneur and Ubuntu founder, Mark Shuttleworth , was quoted in a ZDNet blog article in 2008 about the process of standardization of OOXML as saying: "I think it de-values

2601-420: Was used as a basis for some coding schemes of MPEG-1 and MPEG-2 Audio. Most key features of MPEG-1 Audio were directly inherited from MUSICAM, including the filter bank, time-domain processing, audio frame sizes, etc. However, improvements were made, and the actual MUSICAM algorithm was not used in the final MPEG-1 Audio Layer II standard. Since the finalisation of MPEG-1 Audio and MPEG-2 Audio (in 1992 and 1994),

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