HOME





Audio Lossless Coding
MPEG-4 Audio Lossless Coding, also known as MPEG-4 ALS, is an extension to the MPEG-4 Part 3 audio standard to allow lossless audio compression. The extension was finalized in December 2005 and published as ISO/ IEC 14496-3:2005/Amd 2:2006 in 2006. The latest description of MPEG-4 ALS was published as subpart 11 of the MPEG-4 Audio standard (ISO/IEC 14496-3:2019) (5th edition) in December 2019. MPEG-4 ALS combines a short-term predictor and a long term predictor. The short-term predictor is similar to FLAC in its operation – it is a quantized LPC predictor with a losslessly coded residual using Golomb Rice Coding or Block Gilbert Moore Coding (BGMC). The long term predictor is modeled by 5 long-term weighted residues, each with its own lag (delay). The lag can be hundreds of samples. This predictor improves the compression for sounds with rich harmonics (containing multiples of a single fundamental frequency, locked in phase) present in many musical instruments and human vo ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

International Organization For Standardization
The International Organization for Standardization (ISO ; ; ) 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 the ISO Statutes. ISO was founded on 23 February 1947, and () 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 the International Electrotechnical Commission.Editors of Encyclopedia Britannica. 3 June 2021.Inte ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Reference Implementation (computing)
In the software development process, a reference implementation (or, less frequently, sample implementation or model implementation) is a program that implements all requirements from a corresponding specification. The reference implementation often accompanies a technical standard, and demonstrates what should be considered the "correct" behavior of any other implementation of it. Characteristics and examples Reference implementations of algorithms, for instance cryptographic algorithms, are often the result or the input of standardization processes. In this function they are often dedicated to the public domain with their source code as public domain software. Examples are the first CERN's httpd, Serpent cipher, base64 variants, and SHA-3. The Openwall Project maintains a list of several algorithms with their reference source code In computing, source code, or simply code or source, is a plain text computer program written in a programming language. A programmer w ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Lossless Transform Audio Compression
Lossless Transform Audio Compression (LTAC) is a compression algorithm developed by Tilman Liebchen, Marcus Purat and Peter Noll at Institute for Telecommunications, Technische Universität Berlin (TU Berlin), to compress PCM audio in a lossless manner, ''unlike'' conventional lossy audio compression algorithms (like MP3). LTAC will not be developed any further since it has been superseded by its successor lossless predictive audio compression (LPAC), which is based on linear prediction. This makes it much faster than LTAC and even leads to better compression results. LPAC has become official standard as MPEG-4 Audio Lossless Coding MPEG-4 Audio Lossless Coding, also known as MPEG-4 ALS, is an extension to the MPEG-4 Part 3 audio standard to allow lossless audio compression. The extension was finalized in December 2005 and published as ISO/ IEC 14496-3:2005/Amd 2:2006 in 2 .... References External links Lossless Transform Coding (LTAC) of Audio Signals {{Sound-tech-s ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Nippon Telegraph And Telephone
(NTT) is a Japanese telecommunications holding 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. In 2023, the company was ranked 56th in the Forbes Global 2000. NTT was the world's largest company by market capitalization in the late 1980s, and remained among the world's top 10 largest companies by market capitalization until the burst of the Dot-com bubble in the early 2000s. The company traces its origin to the national telegraph service established in 1868, which came under the purview of the Ministry of Communications in the 1880s. In 1952, the telegraph and telephone services were spun off as the government-owned . Under Prime Minister Yasuhiro Nakasone, the company was privatised in 1985 along with the Japanese National Railways and the Japan Tobacco a ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

RealNetworks
RealNetworks LLC is an American technology company and provider of Internet streaming media delivery software and services based in Seattle, Washington. The company also provides subscription-based online entertainment services and mobile entertainment and messaging services. History RealNetworks (then known as Progressive Networks) was founded in 1994 by Rob Glaser, an ex-Microsoft executive, and a management team including Phil Barrett, Andy Sharpless, and Stephen Buerkle. The original goal of the company was to provide a distribution channel for politically progressive content. It evolved into a technology venture to leverage the Internet as an alternative distribution medium for audio broadcasts. Progressive Networks became RealNetworks in September 1997, in advance of the company's initial public offering (IPO) in October 1997 when shares of the company started trading on Nasdaq as "RNWK". RealNetworks were pioneers in the streaming media markets and broadcast one of the ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Technische Universität Berlin
(TU Berlin; also known as Berlin Institute of Technology and Technical University of Berlin, although officially the name should not be translated) is a public university, public research university located in Berlin, Germany. It was the first German university to adopt the name "Technische Universität" (university of technology). The university alumni and staff includes several United States National Academies, US National Academies members, two National Medal of Science laureates, the creator of the first fully functional programmable (electromechanical) computer, Konrad Zuse, and ten Nobel Prize laureates. TU Berlin is a member of TU9, an incorporated society of the largest and most notable German institutes of technology and of the Top International Managers in Engineering network, which allows for student exchanges between leading engineering schools. It belongs to the Conference of European Schools for Advanced Engineering Education and Research. The TU Berlin is home of ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Moving Picture Experts Group
The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by ISO and IEC that sets standards for media coding, including compression coding of audio, video, graphics, and genomic data; and transmission and file formats for various applications.John Watkinson, ''The MPEG Handbook'', p. 1 Together with JPEG, MPEG is organized under ISO/IEC JTC 1/ SC 29 – ''Coding of audio, picture, multimedia and hypermedia information'' (ISO/IEC Joint Technical Committee 1, Subcommittee 29). MPEG formats are used in various multimedia systems. The most well known older MPEG media formats typically use MPEG-1, MPEG-2, and MPEG-4 AVC media coding and MPEG-2 systems transport streams and program streams. Newer systems typically use the MPEG base media file format and dynamic streaming (a.k.a. MPEG-DASH). History MPEG was established in 1988 by the initiative of Dr. Hiroshi Yasuda ( NTT) and Dr. Leonardo Chiariglione ( CSELT). Chiariglione was th ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Open-source Software
Open-source software (OSS) is Software, computer software that is released under a Open-source license, license in which the copyright holder grants users the rights to use, study, change, and Software distribution, distribute the software and its source code to anyone and for any purpose. Open-source software may be developed in a collaborative, public manner. Open-source software is a prominent example of open collaboration, meaning any capable user is able to online collaboration, participate online in development, making the number of possible contributors indefinite. The ability to examine the code facilitates public trust in the software. Open-source software development can bring in diverse perspectives beyond those of a single company. A 2024 estimate of the value of open-source software to firms is $8.8 trillion, as firms would need to spend 3.5 times the amount they currently do without the use of open source software. Open-source code can be used for studying and a ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

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 video and audio files. It is widely used for format transcoding, basic editing (trimming and concatenation), video scaling, video post-production effects, and standards compliance ( SMPTE, ITU). FFmpeg also includes other tools: ffplay, a simple media player, and ffprobe, a command-line tool to display media information. Among included libraries are libavcodec, an audio/video codec library used by many commercial and free software products, libavformat (Lavf), an audio/video container mux and demux library, and libavfilter, a library for enhancing and editing filters through a GStreamer-like filtergraph. FFmpeg is part of the workflow of many other software projects, and its libraries are a core part of software media players such as V ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Winamp
Winamp is a media player (software), media player for Microsoft Windows originally developed by Justin Frankel and Dmitry Boldyrev by their company Nullsoft, which they later sold to AOL in 1999 for $80 million. It was then acquired by Radionomy in 2014, now known as the Radionomy, Llama Group. Since version 2, it has been sold as freemium and supports extensibility with plug-in (computing), plug-ins and skin (computing), skins, and features music visualization, playlist and a media library, supported by a large online community. Version 1 of Winamp was released in 1997, and quickly grew popular with over 3 million downloads, paralleling the developing trend of MP3 file sharing. Winamp 2.0 was released on September 8, 1998. The 2.x versions were widely used and made Winamp one of the most downloaded Windows applications. By 2000, Winamp had over 25 million registered users and by 2001 it had 60 million users. A poor reception to the 2002 rewrite, Winamp3, was followed ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]