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Vorbis
Vorbis is a free and open-source software project headed by the Xiph.Org Foundation. The project produces an audio coding format and software reference encoder/decoder ( codec) for lossy audio compression, libvorbis. Vorbis is most commonly used in conjunction with the Ogg container format and it is therefore often referred to as Ogg Vorbis. Version 1.0 of Vorbis was released in May 2000. Since 2013, the Xiph.Org Foundation has stated that the use of Vorbis should be deprecated in favor of the Opus codec, an improved and more efficient format that has also been developed by Xiph.Org. Name Vorbis is named after the character Exquisitor Vorbis in the '' Discworld'' novel '' Small Gods'' by Terry Pratchett. The Ogg format is named after ''ogging'', jargon from the computer game '' Netrek''. Development Vorbis is a continuation of audio compression development started in 1993 by Chris Montgomery. Intensive development began following a September 1998 letter from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small Gods
''Small Gods'' is the thirteenth of Terry Pratchett's ''Discworld'' novels, published in 1992. It tells the origin of the god Om, and his relations with his prophet, the reformer Brutha. In the process, it satirises philosophy, religious institutions, people, and practices, and the role of religion in political life. Plot background Omnia is a theocracy based on the Seven Books of the Prophets of Om, collectively known as the ''Septateuch''. The Discworld is flat and is orbited by its sun, but Omnian doctrine says that the world is round and orbits the sun. Omnians believe in a single god, Om, though the Discworld has many gods, including the billions of Small Gods who exist as points of desire searching for believers. Om was once a Small God, but managed to speak to a shepherd, gained believers (despite the shepherd being stoned to death) and took over from Ur-Gilash as the God of what became Omnia. In Omnian tradition there is a new Prophet every two hundred years. Plot T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opus (audio Format)
Opus is a Lossy audio compression, lossy audio coding format developed by the Xiph.Org Foundation and standardized by the Internet Engineering Task Force, designed to efficiently speech coding, code speech and general audio in a single format, while remaining latency (audio), low-latency enough for real-time interactive communication and low-complexity enough for low-end embedded processors. Opus replaces both Vorbis and Speex for new applications. Opus combines the speech-oriented Linear predictive coding, LPC-based SILK algorithm and the lower-latency Modified discrete cosine transform, MDCT-based CELT algorithm, switching between or combining them as needed for maximal efficiency. Bitrate, audio bandwidth, complexity, and algorithm can all be adjusted seamlessly in each frame. Opus has the low algorithmic delay (26.5 ms by default) necessary for use as part of a real-time communication link, networked music performances, and live lip sync; by trading off quality or bitrat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xiph
The Xiph.Org Foundation is a nonprofit organization that produces free software, free multimedia formats and software tools. It focuses on the Ogg family of formats, the most successful of which has been Vorbis, an open and freely licensed audio format and codec designed to compete with the patented Windows Media Audio, WMA, MP3 and Advanced audio coding, AAC. As of 2013, development work was focused on Daala, an open and patent-free video format and codec designed to compete with VP9 and the patented High Efficiency Video Coding. In addition to its in-house development work, the foundation has also brought several already-existing but complementary free software projects under its aegis, most of which have a separate, active group of developers. These include Speex, an audio codec designed for speech, and Free Lossless Audio Codec, FLAC, a lossless audio codec. The Xiph.Org Foundation has criticized Microsoft and the Recording Industry Association of America, RIAA for their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Audio Coding Format
An audio coding format (or sometimes audio compression format) is a content representation format for storage or transmission of digital audio (such as in digital television, digital radio and in audio and video files). Examples of audio coding formats include MP3, AAC, Vorbis, FLAC, and Opus. A specific software or hardware implementation capable of audio compression and decompression to/from a specific audio coding format is called an '' audio codec''; an example of an audio codec is LAME, which is one of several different codecs which implements encoding and decoding audio in the MP3 audio coding format in software. Some audio coding formats are documented by a detailed technical specification document known as an audio coding specification. Some such specifications are written and approved by standardization organizations as technical standards, and are thus known as an audio coding standard. The term "standard" is also sometimes used for ''de facto'' standards as wel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WebM
WebM is an audiovisual media file format. It is primarily intended to offer a royalty-free alternative to use in the HTML video and the HTML audio elements. It has a sister project, WebP, for images. The development of the format is sponsored by Google, and the corresponding software is distributed under a BSD licenses, BSD license. The WebM Digital container format, container is based on a Profile (engineering), profile of Matroska. WebM initially supported VP8 video and Vorbis audio streams. In 2013, it was updated to accommodate VP9 video and Opus (audio format), Opus audio. It also supports the AV1 codec. Vendor support Software Native WebM support by Firefox, Mozilla Firefox, Opera (web browser), Opera, and Google Chrome was announced at the 2010 Google I/O conference. Internet Explorer 9 requires third-party WebM software. In 2021, Apple Inc., Apple released Safari (web browser), Safari 14.1 for macOS, which added native WebM support to the browser. , QuickTime does n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Audio File Format
An audio file format is a file format for storing digital audio data on a computer system. The bit layout of the audio data (excluding metadata) is called the audio coding format and can be uncompressed, or audio compression (data), compressed to reduce the file size, often using lossy compression. The data can be a raw bitstream in an audio coding format, but it is usually embedded in a container format or an audio data format with defined storage layer. Format types It is important to distinguish between the audio coding format, the Container format (digital), container containing the Raw audio format, raw audio data, and an audio codec. A codec performs the encoding and decoding of the raw audio data while this encoded data is (usually) stored in a container file. Although most audio file formats support only one type of audio coding data (created with an audio codec, audio coder), a multimedia container format (as Matroska or Audio Video Interleave, AVI) may support multiple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lossy Compression
In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data size for storing, handling, and transmitting content. Higher degrees of approximation create coarser images as more details are removed. This is opposed to lossless data compression (reversible data compression) which does not degrade the data. The amount of data reduction possible using lossy compression is much higher than using lossless techniques. Well-designed lossy compression technology often reduces file sizes significantly before degradation is noticed by the end-user. Even when noticeable by the user, further data reduction may be desirable (e.g., for real-time communication or to reduce transmission times or storage needs). The most widely used lossy compression algorithm is the discrete cosine transform (DCT), first published by N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chris Montgomery
Christopher "Monty" Montgomery (born June 6, 1972) is an American programmer and engineer. He is the original creator of the Ogg Free Software container format and the Vorbis audio codec and others, and the founder of Xiph.Org Foundation, The Xiph.Org Foundation, which promotes public domain multimedia codecs. He uses ''xiphmont'' as an online pseudonym. He holds a Bachelor of Science, B.S. in electrical engineering and computer science from the Massachusetts Institute of Technology and a Master of Engineering, M.Eng. degree in computer engineering from the Tokyo Institute of Technology. A multimedia programmer, free software advocate and musician, Monty resides in the Boston area. He previously worked for Red Hat on improving the quality of the Ogg Theora format and decoders. In October 2013, he announced his almost immediate switch to Mozilla Foundation, Mozilla. Work on Daala will be an important part of his work there. Montgomery was the evening keynote at the Ohio LinuxFe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Audio Compression (data)
In information theory, data compression, source coding, or bit-rate reduction is the process of encoding information using fewer bits than the original representation. Any particular compression is either lossy or lossless. Lossless compression reduces bits by identifying and eliminating Redundancy (information theory), statistical redundancy. No information is lost in lossless compression. Lossy compression reduces bits by removing unnecessary or less important information. Typically, a device that performs data compression is referred to as an encoder, and one that performs the reversal of the process (decompression) as a decoder. The process of reducing the size of a data file is often referred to as data compression. In the context of data transmission, it is called source coding: encoding is done at the source of the data before it is stored or transmitted. Source coding should not be confused with channel coding, for error detection and correction or line coding, the means ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Container Format
A container format (informally, sometimes called a wrapper) or metafile is a file format that allows multiple data streams to be embedded into a single file, usually along with metadata for identifying and further detailing those streams. Notable examples of container formats include archive files (such as the ZIP format) and formats used for multimedia playback (such as Matroska, MP4, and AVI). Among the earliest cross-platform container formats were Distinguished Encoding Rules and the 1985 Interchange File Format. Design Although containers may identify how data or metadata is encoded, they do not actually provide instructions about how to decode that data. A program that can open a container must also use an appropriate codec to decode its contents. If the program doesn't have the required algorithm, it can't use the contained data. In these cases, programs usually emit an error message that complains of a missing codec, which users may be able to acquire. Container ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matroska
Matroska (styled Matroška) is a project to create a container format that can hold an unlimited number of video, audio, picture, or subtitle tracks in one file. The Matroska Multimedia Container is similar in concept to other containers like AVI, MP4, or Advanced Systems Format (ASF), but is an open standard. Matroska file extensions are ''.mkv'' for video (which may include subtitles or audio), ''.mk3d'' for stereoscopic video, ''.mka'' for audio-only files (which may include subtitles), and ''.mks'' for subtitles only. History The project was announced on 6 December 2002 as a fork of the Multimedia Container Format (MCF), after disagreements between MCF lead developer Lasse Kärkkäinen and soon-to-be Matroska founder Steve Lhomme about the use of the Extensible Binary Meta Language (EBML) instead of a binary format. This coincided with a 6-month coding break by the MCF's lead developer for his military service, during which most of the community quickly migrated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
