NationMaster - Encyclopedia: Dolby Digital

Dolby Digital is the marketing name for a series of lossy audio compression technologies by Dolby Laboratories. A lossy data compression method is one where compressing data and then decompressing it retrieves data that may well be different from the original, but is close enough to be useful in some way. ... Dolby Laboratories, Inc. ...

Versions

Dolby Digital includes several similar technologies. A digital system is one that uses discrete values (often electrical voltages), especially those representable as binary numbers, or non-numeric symbols such as letters or icons, for input, processing, transmission, storage, or display, rather than a continuous spectrum of values (ie, as in an analog system). ...

Dolby Digital

Dolby Digital, or AC-3, is the common version containing up to six discrete channels of sound, with five channels for normal-range speakers (20 Hz – 20,000 Hz) (Right front, Center, Left Front, Right Rear and Left Rear) and one channel (20 Hz – 120 Hz) for the subwoofer driven low frequency effects. The Dolby Digital format supports mono and stereo usages as well. Batman Returns was the first film to use the Dolby Digital technology when it premiered in theaters in Summer 1992. The LaserDisc version of Clear and Present Danger featured the very first Home Theater Dolby Digital mix in 1995. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... a 12 subwoofer driver A subwoofer is a type of driver dedicated to the reproduction of bass frequencies, typically from about 20 Hz to perhaps 200 Hz in cone speakers, and in the case of a rotary woofer, all the way down to below 1 Hz. ... LFE is an abbreviation that is commonly used in describing an audio track contained within a 5. ... Monaural (often shortened to mono) sound reproduction is single-channel. ... Label for 2. ... Batman Returns is a 1992 motion picture based on the Batman character created by Bob Kane and Bill Finger. ... Clear and present danger is a term used in the case Schenck v. ...

This codec has several aliases, which are different names for the same codec: A codec is a device or program capable of performing encoding and decoding on a digital data stream or signal. ...

The Advanced Television Systems Committee (ATSC) is the group that helped to develop the new digital television standard for the United States, also adopted by Canada, Mexico, and South Korea and being considered by other countries. ... True Lies is a 1994 action/comedy remake of the 1991 French film La Totale!. It was directed by James Cameron, and stars Arnold Schwarzenegger, Jamie Lee Curtis, Tom Arnold, Bill Paxton, Tia Carrere, Charlton Heston and Art Malik. ... Dolby Analog SR or Dolby SR format (Spectral Recording), was developed by Dolby Laboratories and has been in common use in professional audio since 1986. ... A bitstream or bit stream is a time series of bits. ... A backronym or bacronym is a portmanteau of backward and acronym[1] coined in 1983. ... ATRAC (Adaptive TRansform Acoustic Coding) is an audio compression algorithm used to store information on Minidiscs and other Sony_branded audio players. ... Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $68. ...

Dolby Digital EX

Dolby Digital EX is similar in practice to Dolby's earlier Pro-Logic format, which utilized Matrix technology to add a center and single rear surround channel to stereo soundtracks. EX adds an extension to the standard 5.1 channel Dolby Digital codec in the form of matrixed rear channels, creating 6.1 or 7.1 channel output. However, the format is not considered a true 6.1 or 7.1 channel codec because it lacks the capability to support a discrete 6th channel unlike the competing DTS-ES codec. It has been suggested that this article or section be merged with Dolby Surround. ... In sound recording, a matrix can refer to a disc in the early stages of processing a record for mass production; see mastering and pressing process discussion at gramophone record. ... DTS DTS (formerly known as Digital Theater Systems), owned by DTS Inc (NASDAQ: DTSI), is a multi-channel surround sound format used for both commercial/theatrical and consumer grade applications (with significant technical differences between home and commercial/theatrical variants: the latter being a traditional ADPCM compression system and the...

Dolby Digital Live

Dolby Digital Live (DDL) is a real-time encoding technology for interactive media such as video games. It converts any audio signals on a PC or game console into the 5.1-channel Dolby Digital format and transports it via a single S/PDIF cable.^[1] The SoundStorm, used for the Xbox game console and certain nForce2-based PCs, used an early form of this technology. Dolby Digital Live is currently available in sound cards from manufacturers such as Turtle Beach^[2] and Auzentech^[3] using C-Media chipsets, as well as on motherboards with codecs such as Realtek's ALC882D^[4], ALC888DD and ALC888H ^[5] A similar technology known as DTS Connect is available from competitor DTS. This article is about computer and video games. ... The Altair 8800 was among the first microcomputers to be affordable by an individual, although it initially lacked peripherals and memory. ... Four different video game consoles from different generations. ... S/PDIF or S/P-DIF stands for Sony/Philips Digital Interface Format, also IEC 958 type II, part of IEC-60958. ... SoundStorm was an advanced integrated 5. ... The Xbox is a sixth generation era video game console produced by Microsoft Corporation. ... The nForce2 Chipset was released by NVIDIA in July of 2002 as a refresh to the original nForce product offering. ... A sound card is a computer expansion card that can input and output sound under control of computer programs. ... Turtle Beach Systems is a sound card and headphone manufacturer and direct competitor with Creative Labs-branded Sound Blaster. ... There are very few or no other articles that link to this one. ... Realtek Semiconductor Corp. ... DTS (formerly known as Digital Theater Systems), owned by DTS, Inc. ...

Dolby Digital Surround EX

Dolby Digital Surround EX was co-developed by Dolby and Lucasfilm THX in time for the release in May 1999 of Star Wars Episode I: The Phantom Menace. It provides an economical and backwards-compatible means for 5.1 soundtracks to carry a sixth, center back surround channel for improved localization of effects. The extra surround channel is matrix encoded onto the discrete Left Surround and Right Surround channels of the 5.1 mix, much like the front center channel on Dolby Surround encoded stereo soundtracks. The result can be played without loss of information on standard 5.1 systems, or played in 6.1 or 7.1 on systems equipped with Surround EX decoding and additional speakers. Dolby Digital Surround EX has since been used for the Star Wars prequels on the DVD versions and also the remastered original Star Wars trilogy. A number of DVDs have Dolby Digital Surround EX audio option. Dolby Laboratories, Incorporated (Dolby Labs) is a company specializing in audio compression and reproduction. ... Lucasfilm Ltd. ... THX logo This article is about the sound-system standard promulgated by George Lucas company. ... Film poster for Star Wars Episode I: The Phantom Menace Star Wars Episode I: The Phantom Menace is a 1999 film by George Lucas starring Liam Neeson, Ewan McGregor, Natalie Portman, and Jake Lloyd. ... This article needs additional references or sources to facilitate its verification. ...

Dolby Digital Plus

E-AC-3, more commonly known as Dolby Digital Plus, is an enhanced coding system based on the AC-3 codec. It offers increased bitrates (up to 6.144 Mbit/s), support for more audio channels (up to 13.1), improved coding techniques to reduce compression artifacts, and backward compatibility with existing AC-3 hardware. Dolby Digital Plus (DD+), also known as E-AC-3, was developed specifically for the introduction of HDTV and HD-DVD/Blu-ray discs. ... A compression artifact is a particular type of data error that is typically the result of quantization in lossy data compression. ...

Dolby TrueHD

Dolby TrueHD, from Dolby Laboratories, is an advanced lossless audio codec based on Meridian Lossless Packing. Support for the codec is mandatory for HD DVD and optional for Blu-ray Disc hardware. TrueHD supports 24 bit, 96 kHz audio channels at up to 18 Mbit/s over 8 channels (although HD DVD and Blu-ray Disc standards currently limit their maximum number of audio channels to eight, Dolby TrueHD can output up to 14 sound channels simultaneously). It also supports extensive metadata, including dialog normalization and Dynamic Range Control. Dolby TrueHD logo Dolby TrueHD, from Dolby Laboratories, is an advanced lossless multi-channel audio codec, intended primarily for high-end home-entertainment equipment, such as Blu-ray Disc and HD DVD. In this application, Dolby TrueHD competes with DTS-HD Master Audio, another lossless codec from Digital Theater System. ... Meridian Lossless Packing is a proprietary lossless compression technique for compressing PCM audio data. ... A Blu-ray Disc (also called BD) is a high-density optical disc format for the storage of digital media, including high-definition video. ...

Channel configurations

Although most commonly associated with the 5.1 channel configuration, Dolby Digital allows a number of different channel selections. The full list of available options is:

All of these configurations can optionally include the extra Low Frequency Effect (LFE) channel. The last two with stereo surrounds can optionally use Dolby Digital EX matrix encoding to add an extra Rear Surround channel.

Many Dolby Digital decoders are equipped with downmixing functionality to distribute encoded channels to available speakers. This includes such functions as playing surround information through the front speakers if surround speakers are unavailable, and distributing the center channel to left and right if no center speaker is available. When outputting to separate equipment over a 2-channel connection, a Dolby Digital decoder can optionally encode the output using Dolby Surround to preserve surround information.

The '.1' in 5.1, 7.1 etc. refers to the LFE channel, which is also a discrete channel. LFE is an abbreviation that is commonly used in describing an audio track contained within a 5. ...

Applications of Dolby Digital

Dolby Digital SR-D cinema soundtracks are optically recorded on a 35 mm release print using sequential data blocks placed between every perforation hole on the sound track side of the film. A CCD scanner in the projector picks up a scanned video image of this area, and a processor correlates the image area and extracts the digital data as an AC-3 bitstream. These data are finally decoded into a 5.1 channel audio source. Image File history File linksMetadata Download high resolution version (1914x1393, 459 KB) Summary Macro of 35mm film audio tracks, from left to right: Sony SDDS, Dolby Digital, analog Optical, and finally DTS time code. ... Image File history File linksMetadata Download high resolution version (1914x1393, 459 KB) Summary Macro of 35mm film audio tracks, from left to right: Sony SDDS, Dolby Digital, analog Optical, and finally DTS time code. ... SDDS stands for Sony Dynamic Digital Sound, which is a cinema sound system developed by Sony. ... // In film formats, the sound track is the physical area of the film which records the synchronized sound. ... Simulated 35 mm film with soundtracks _ The outermost strips (on either side) contain the SDDS soundtrack as an image of a digital signal. ... A release print is the reel of film that is sent to a movie theater for exhibition. ... Film is a term that encompasses individual motion pictures, the field of film as an art form, and the motion picture industry. ... A specially developed CCD used for ultraviolet imaging in a wire bonded package. ... Projectors are used for displaying an image on a projection screen or similar surface for the view of an audience. ... A digital system is one that uses discrete values (often electrical voltages), especially those representable as binary numbers, or non-numeric symbols such as letters or icons, for input, processing, transmission, storage, or display, rather than a continuous spectrum of values (ie, as in an analog system). ...

Dolby Digital audio is also used on DVD-Video and other purely digital media, like home cinema. In this format, the AC-3 bitstream is interleaved with the video and control bitstreams. The DVD-Video format logo. ... Bold textDigital media (as opposed to analog media) usually refers to electronic media that work on digital codes. ... A 3 metres/119 inch projection screen with a high-definition television image. ...

The system is used in many bandwidth-limited applications other than DVD-Video, such as digital TV. The AC-3 standard allows a maximum coded bit rate of 640 kbit/s. 35 mm film prints use a fixed rate of 320 kbit/s. HD-DVD and DVD-Video discs are limited to 448 kbit/s, although many players can successfully play higher-rate bitstreams (which are non-compliant with the DVD specification). ATSC and Digital cable TV standards limit AC-3 to 448 kbit/s. Both Blu-ray Disc, the Sony PlayStation 3 and the Microsoft Xbox game console can output an AC-3 signal at a full 640 kbit/s. Some Sony PlayStation 2 console games are also capable to output AC-3 standard audio as well. A kilobit per second (kbit/s or kbps or kBaud) is a unit of data transfer rate equal to 1,000 bits per second. ... The Advanced Television Systems Committee (ATSC) is the group that helped to develop the new digital television standard for the United States, also adopted by Canada, Mexico, and South Korea and being considered by other countries. ... Cable television or Community Antenna Television (CATV) (and often shortened to cable) is a system of providing television, FM radio programming and other services to consumers via radio waves transmitted directly to people’s televisions through fixed coaxial cables as opposed to the over-the-air method used in... A Blu-ray Disc (also called BD) is a high-density optical disc format for the storage of digital media, including high-definition video. ... Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $68. ... PlayStation 3 , trademarked PLAYSTATIONÂ®3,[7] commonly abbreviated PS3) is Sony Computer Entertainments third video game console. ... Microsoft Corporation, (NASDAQ: MSFT, HKSE: 4338) is a multinational computer technology corporation with global annual revenue of US$44. ... The Xbox is a sixth generation era video game console produced by Microsoft Corporation. ... The Nintendo GameCube is an example of a popular video game console. ... Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $68. ... The PlayStation 2 , abbreviated PS2) is Sonys second video game console, the successor to the PlayStation and the predecessor to the PlayStation 3. ...

In certain console and PC games, for example, games from the Sony PlayStation 2 console platform, is capable to output real time Dolby Pro Logic or Dolby Pro Logic II audio during game play. Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $68. ... The PlayStation 2 , abbreviated PS2) is Sonys second video game console, the successor to the PlayStation and the predecessor to the PlayStation 3. ...

Dolby is part of a group of organizations involved in the development of AAC (Advanced Audio Coding), part of MPEG specifications, and also considered the successor to MP3. AAC outperforms AC-3 at any bitrate, but is more complex. The advantages of AAC become clearly audible at less than 400 kbit/s for 5.1 channels, and at less than 180 kbit/s for 2.0 channels. Advanced Audio Coding (AAC) is a standardized, lossy compression and encoding scheme for digital audio. ... The Moving Picture Experts Group or MPEG is a working group of ISO/IEC charged with the development of video and audio encoding standards. ... MPEG-1 Audio Layer 3, more commonly referred to as MP3, is a popular digital audio encoding format. ...

Dolby Digital Plus (DD-Plus) is supported in HD DVD, as a mandatory codec, and in Blu-ray Disc, as an optional codec. HD-DVD disc HD DVD (for High Density Digital Versatile Disc) is a digital optical media format which is being developed as one standard for high-definition DVD. HD DVD is similar to the competing Blu-ray Disc, which also uses the same CD sized (120 mm diameter) optical data... A Blu-ray Disc (also called BD) is a high-density optical disc format for the storage of digital media, including high-definition video. ...

Dolby Technologies in packaged media formats

HD-DVD disc HD DVD (for High Density Digital Versatile Disc) is a digital optical media format which is being developed as one standard for high-definition DVD. HD DVD is similar to the competing Blu-ray Disc, which also uses the same CD sized (120 mm diameter) optical data... Blu-ray discs Blu-ray Disc is a next-generation optical disc format jointly developed by a group of leading consumer electronics and PC companies called the Blu_ray Disc Association (BDA), which succeeds the Blu_ray Disc Founders (BDF). ... DVD (also known as Digital Versatile Disc or Digital Video Disc) is an optical disc storage media format that can be used for data storage, including movies with high video and sound quality. ... The DVD-Audio logo. ... Dolby Digital Plus (DD+), also known as E-AC-3, was developed specifically for the introduction of HDTV and HD-DVD/Blu-ray discs. ... Dolby TrueHD logo Dolby TrueHD, from Dolby Laboratories, is an advanced lossless multi-channel audio codec, intended primarily for high-end home-entertainment equipment, such as Blu-ray Disc and HD DVD. In this application, Dolby TrueHD competes with DTS-HD Master Audio, another lossless codec from Digital Theater System. ...

See also

Dialnorm is the meta-data parameter that controls decoder gain within the proprietary Dolby Laboratories Dolby Digital (AC-3) audio compression system. ... Dolby Laboratories, Inc. ... Dolby NR is a noise reduction system developed by Dolby Laboratories for use in analogue magnetic tape recording. ... Typical 60-minute Compact Cassette. ... Sign for Dolby Stereo Dolby Stereo (or Dolby Analog) was the original analog optical technology developed by Dolby Laboratories for 35 mm prints in 1976. ... It has been suggested that this article or section be merged with Dolby Surround. ... Dolby TrueHD logo Dolby TrueHD, from Dolby Laboratories, is an advanced lossless multi-channel audio codec, intended primarily for high-end home-entertainment equipment, such as Blu-ray Disc and HD DVD. In this application, Dolby TrueHD competes with DTS-HD Master Audio, another lossless codec from Digital Theater System. ... HD-DVD disc HD DVD (for High Density Digital Versatile Disc) is a digital optical media format which is being developed as one standard for high-definition DVD. HD DVD is similar to the competing Blu-ray Disc, which also uses the same CD sized (120 mm diameter) optical data... A Blu-ray Disc (also called BD) is a high-density optical disc format for the storage of digital media, including high-definition video. ... A 3 metres/119 inch projection screen with a high-definition television image. ... This article or section needs copy editing for grammar, style, cohesion, tone and/or spelling. ... SoundStorm was an advanced integrated 5. ... The nForce2 Chipset was released by NVIDIA in July of 2002 as a refresh to the original nForce product offering. ... There are very few or no other articles that link to this one. ...

Technical details

The data layout of AC-3 is described by simplified "C" like language in official specifications. An AC-3 stream is made up by a series of synchronization frames, which are composed of six audio blocks. Each audio block contains 256 audio samples per channel. Note 6×256 = 1536 = Audio frame size. Below is a simplified AC-3 header intended to give an introduction into the data syntax. A detailed description of the header can be found in the ATSC "Digital Audio Compression (AC-3) Standard", section 5.4. C is a general-purpose, procedural, imperative computer programming language developed in 1972 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system. ...

In computing a syncword is used to synchronize data. ... When integers or any other data are represented with multiple bytes, there is no unique way of ordering of those bytes in memory or in a transmission over some medium, and so the order is subject to arbitrary convention. ... A cyclic redundancy check (CRC) is a type of hash function used to produce a checksum â€“ a small, fixed number of bits â€“ against a block of data, such as a packet of network traffic or a block of a computer file. ... The sampling frequency or sampling rate defines the number of samples per second taken from a continuous signal to make a discrete signal. ...

References

External links

Multimedia compression formats

v • d • e

Video compression formats

ISO/IEC

MJPEG · MPEG-1 · MPEG-2 · MPEG-4 ASP · MPEG-4/AVC

ITU-T

H.261 · H.262 · H.263 · H.264

Others

AVS · Bink · Dirac · Indeo · MJPEG · RealVideo · Theora · VC-1 · VP6 · VP7 · WMV

Audio compression formats

ISO/IEC MPEG

MPEG-1 Layer III (MP3) · MPEG-1 Layer II · MPEG-1 Layer I · AAC · HE-AAC

ITU-T

G.711 · G.722 · G.722.1 · G.722.2 · G.723 · G.723.1 · G.726 · G.728 · G.729 · G.729.1 · G.729a

Others

AC3 · Apple Lossless · ATRAC · FLAC · iLBC · Monkey's Audio · μ-law · Musepack · Nellymoser · RealAudio · SHN · Speex · Vorbis · WavPack · WMA · TAK

Image compression formats

ISO/IEC/ITU-T

JPEG · JPEG 2000 · lossless JPEG · JBIG · JBIG2 · PNG · WBMP

Others

APNG · ICER · MNG · BMP · GIF · ILBM · PCX · TGA · TIFF · HD Photo

Media container formats

General

3GP · ASF · AVI · DMF · DPX · FLV · Matroska · MP4 · MXF · NUT · Ogg · Ogg Media · QuickTime · RealMedia · VOB

Audio only

AIFF · AU · WAV

Codecs implementations

v • d • e

Video codecs
(Comparison)

MPEG-4 ASP

3ivx · DivX · FFmpeg MPEG-4 · HDX4 · Xvid

H.264/MPEG-4 AVC

CoreAVC · QuickTime H.264 · x264 ... In computer science and information theory, data compression or source coding is the process of encoding information using fewer bits (or other information-bearing units) than an unencoded representation would use through use of specific encoding schemes. ... Video compression refers to making a digital video signal use less data, without noticeably reducing the quality of the picture. ... This article or section does not cite any references or sources. ... The International Electrotechnical Commission (IEC) is an international standards organization dealing with electrical, electronic and related technologies. ... Motion JPEG (M-JPEG) is an informal name for multimedia formats where each video frame or interlaced field of a digital video sequence is separately compressed as a JPEG image. ... MPEG-1 defines a group of Audio and Video (AV) coding and compression standards agreed upon by MPEG (Moving Picture Experts Group). ... MPEG-2 is a standard for the generic coding of moving pictures and associated audio information [1]. It is widely used around the world to specify the format of the digital television signals that are broadcast by terrestrial (over-the-air), cable, and direct broadcast satellite TV systems. ... MPEG-4 Part 2 is a video compression technology developed by MPEG. It belongs to the MPEG-4 ISO/IEC standard (ISO/IEC 14496-2). ... H.264 is a standard for video compression. ... The ITU Telecommunication Standardization Sector (ITU-T) coordinates standards for telecommunications on behalf of the International Telecommunication Union (ITU) and is based in Geneva, Switzerland. ... H.261 is an 1990 ITU video coding standard originally designed for transmission over ISDN lines on which data rates are multiples of 64 kbit/s. ... H.262 is an ITU-T digital video coding standard. ... H.263 is a video codec designed by the ITU-T as a low-bitrate encoding solution for videoconferencing. ... H.264 is a standard for video compression. ... The Peoples Republic of China government is supporting an effort to develop own standard for compressing digital audio and video, to assert its technological independence from the rest of the world. ... Bink is a video file format (extension . ... Dirac is a prototype algorithm for the encoding and decoding (see codec) of raw video. ... Indeo Video (commonly known now simply as Indeo) is a video codec developed by Intel in 1992. ... Motion JPEG (M-JPEG) is an informal name for multimedia formats where each video frame or interlaced field of a digital video sequence is separately compressed as a JPEG image. ... RealVideo is a proprietary video format developed by RealNetworks. ... Theora is a video codec being developed by the Xiph. ... VC-1 is the informal name of the SMPTE 421M video codec standard initially developed by Microsoft. ... TrueMotion VP6 is a video codec developed by On2 Technologies as a successor to earlier efforts such as VP3 and VP5. ... TrueMotion VP7 is a video codec developed by On2 Technologies as a successor to earlier efforts such as VP3, VP5 and TrueMotion VP6. ... Windows Media Video (WMV) is a generic name for the set of video codec technologies developed by Microsoft. ... Audio compression is a form of data compression designed to reduce the size of audio files. ... This article or section does not cite any references or sources. ... The International Electrotechnical Commission (IEC) is an international standards organization dealing with electrical, electronic and related technologies. ... The Moving Picture Experts Group or MPEG is a working group of ISO/IEC charged with the development of video and audio encoding standards. ... MPEG-1 Audio Layer 3, more commonly referred to as MP3, is a popular digital audio encoding format. ... MPEG-1 Audio Layer II (MP2, sometimes Musicam) is an audio codec defined by ISO/IEC 11172-3. ... MPEG-1 Audio Layer I, commonly abbreviated to MP1, is one of three audio codecs included in the MPEG-1 standard. ... Advanced Audio Coding (AAC) is a standardized, lossy compression and encoding scheme for digital audio. ... High Efficiency AAC (HE-AAC) is a lossy data compression scheme for digital audio. ... The ITU Telecommunication Standardization Sector (ITU-T) coordinates standards for telecommunications on behalf of the International Telecommunication Union (ITU) and is based in Geneva, Switzerland. ... G.711 is an ITU-T standard for audio companding. ... G.722 is a ITU-T standard wideband speech codec operating at 32-64 kbit/s. ... G.722. ... Adaptive Multi Rate - WideBand or AMR-WB is a speech coding standard developed after the AMR using same technology like ACELP. The codec provides excellent speech quality due to wider speech bandwidth of 50 - 7000 Hz compared to narrowband speech codecs which in general are optimized for POTS wireline quality... This article is in need of attention from an expert on the subject. ... G.723. ... G.726 is ITU-T speech codec operating at bit rates of 16-40 kbit/s. ... G.728 is a ITU-T standard for speech coding operating at 16 kbit/s. ... G.729 is an audio data compression algorithm for voice that compresses voice audio in chunks of 10 milliseconds. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... G.729 is an audio data compression algorithm for voice that compresses voice audio in chunks of 10 milliseconds. ... Apple Lossless (also known as Apple Lossless Encoder, ALE, or Apple Lossless Audio Codec, ALAC) is an audio codec developed by Apple Inc. ... Adaptive Transform Acoustic Coding (ATRAC) is a family of proprietary audio compression algorithms developed by Sony. ... Free Lossless Audio Codec (FLAC) is a popular file format for audio data compression. ... internet Low Bit Rate Codec (iLBC) is a royalty free narrowband speech codec, developed by Global IP Sound (GIPS). ... Monkeyâ€™s Audio is a lossless audio compression codec. ... In telecommunication, a mu-law algorithm (Î¼-law) is a standard analog signal compression or companding algorithm, used in digital communications systems of the North American and Japanese digital hierarchies, to optimize (in other words, modify) the dynamic range of an audio analog signal prior to digitizing. ... Musepack or MPC is an open source lossy audio codec, specifically optimized for transparent compression of stereo audio at bitrates of 160-180 kbit/s. ... This is a single-channel (mono) format optimized for low-bitrate transmission of speech. ... RealAudio is a proprietary audio format developed by RealNetworks. ... SHN (Shorten) is a file format used to losslessly compress CD-quality audio files (44. ... Speex is a free software speech codec that claims to be unencumbered by patent restrictions. ... Vorbis is an open source, lossy audio codec project headed by the Xiph. ... WavPack is a free, open source lossless audio compression format developed by David Bryant. ... Windows Media Audio (WMA) is a proprietary compressed audio file format developed by Microsoft. ... TAK (Toms lossless Audio Kompressor) is a lossless audio compressor which promises compression performance similar to Monkeys Audio High and decompression speed similar to FLAC. The codec also supports streaming (necessary headers for decompressing the audio are written to the stream every 2 seconds), error tolerance (single bit... Image compression is the application of data compression on digital images. ... This article or section does not cite any references or sources. ... The International Electrotechnical Commission (IEC) is an international standards organization dealing with electrical, electronic and related technologies. ... The ITU Telecommunication Standardization Sector (ITU-T) coordinates standards for telecommunications on behalf of the International Telecommunication Union (ITU) and is based in Geneva, Switzerland. ... In computing, JPEG (pronounced JAY-peg; IPA: ) is a commonly used standard method of compression for photographic images. ... JPEG 2000 is a wavelet-based image compression standard. ... The Joint Photographic Experts Group, in addition to their well-known lossy image compression techniques, JPEG and JPEG 2000, also have three standards for lossless compression (of which JPEG-LS has a lossy mode): Lossless JPEG was developed as a late addition to JPEG in 1993, using a completely different... JBIG is a lossless image compression standard from the Joint Bi-level Image Experts Group, standardized as ISO/IEC standard 11544 and as ITU-T recommendation T.82. ... JBIG2 is an image compression standard for bi-level images, developed by the Joint Bi-level Image Experts Group. ... PNG (Portable Network Graphics) is a bitmapped image format that employs lossless data compression. ... Wireless Application Protocol Bitmap Format (shortened to Wireless Bitmap and with file extension . ... The APNG (Animated Portable Network Graphics) file format is an extension to the Portable Network Graphics (PNG) specification proposed by Stuart Parmenter and Vladimir Vukicevic of the Mozilla Corporation. ... ICER is a wavelet-based image compression file format used by the NASA Mars Rovers. ... Multiple-image Network Graphics (MNG) (IPA pronunciation: ) is a public graphics file format for animated images. ... DIB redirects here. ... An example of a GIF image. ... ILBM is a subtype of the Interchange File Format used for storing picture data. ... PCX is an image file format that uses a simple form of run-length encoding (a type of lossless compression algorithm). ... Truevisions TGA File Format, often referred to as TARGA File Format, is a raster graphics file format. ... â€œTIFFâ€ redirects here. ... HD Photo (formerly Windows Media Photo) is a still image compression algorithm and file format for continuous tone photographic images, developed by Microsoft as a part of the Windows Media family. ... A container format is a computer file format that can contain various types of data, compressed by means of standardized codecs. ... 3GP is a multimedia container format defined by the Third Generation Partnership Project (3GPP) for use on 3G mobile phones. ... Advanced Systems Format (formerly Advanced Streaming Format) is Microsofts proprietary digital audio/digital video container format, especially meant for streaming media. ... // Audio Video Interleave, known by its acronym AVI, is a multimedia container format introduced by Microsoft in November 1992 as part of its Video for Windows technology. ... DivX is a video codec created by DivX, Inc. ... DPX, the short form of Digital Picture Exchange, is a common file format for digital film work and is an ANSI/SMPTE standard (268M-2003). ... Flash Video (FLV) is a proprietary file format used to deliver video over the Internet using Adobe Flash Player (formerly known as Macromedia Flash Player) version 6, 7, 8, or 9. ... Matroska (common file extensions being . ... MPEG-4 Part 14, formally ISO/IEC 14496-14:2003, is a multimedia container format standard specified as a part of MPEG-4. ... Material eXchange Format (MXF) is a container format for professional digital video and audio media defined by a set of SMPTE standards. ... NUT is a patent-free, multimedia container format originally conceived by a few MPlayer and FFmpeg developers that were dissatisfied with the limitations of all currently available multimedia container formats such as AVI or Matroska. ... Ogg may refer to: Nanny Ogg, a character in the Discworld series of books Ogg, a minor non-appearing character mentioned in the fantasy book, Harry Potter and the Goblet of Fire Ogg, a multimedia container file format, in computing OGG, the IATA code for Kahului Airport, Hawaii Ogg (Cro... Ogg Media (OGM), meaning Ogg Media File, is a container format (for video, audio and subtitle streams). ... QuickTime is a multimedia framework developed by Apple Inc. ... RealMedia is a multimedia container format created by RealNetworks. ... A VOB file (DVD-Video Object or Versioned Object Base) is a container format contained in DVD-Video media. ... Audio Interchange File Format (AIFF) is an audio file format standard used for storing sound data on personal computers. ... The Au file format is a simple audio file format that consists of a header of 6 32-bit words and then the data (high-order byte comes first). ... WAV (or WAVE), short for Waveform audio format, is a Microsoft and IBM audio file format standard for storing audio on PCs. ... A codec is a device or program capable of performing encoding and decoding on a digital data stream or signal. ... Look up Implementation in Wiktionary, the free dictionary. ... A video codec is a device or software module that enables video compression or decompression for digital video. ... This article or section is in need of attention from an expert on the subject. ... MPEG-4 Part 2 is a video compression technology developed by MPEG. It belongs to the MPEG-4 ISO/IEC standard (ISO/IEC 14496-2). ... 3ivx is a video codec created by 3ivx Technologies. ... DivX is a brand name of products created by DivX, Inc. ... FFmpeg is a collection of free software that can record, convert and stream digital audio and video. ... HDX4 is a MPEG4 codec developed by a German company named Jomigo Visual Technology. ... Xvid (formerly XviD) is a video codec library following the MPEG-4 standard. ... H.264 is a standard for video compression. ... CoreAVC is a video decoder developed by CoreCodec, implementing the MPEG-4 AVC standard (also known as H.264) used, for example, in next-generation video disc formats HD DVD and Blu-Ray. ... QuickTime is a multimedia framework developed by Apple Inc. ... x264 is a free software library for encoding H.264/MPEG-4 AVC video streams. ...

Lossless

CorePNG · FFV1 · Huffyuv · Lagarith · MSU Lossless Lossless data compression is a class of data compression algorithms that allows the exact original data to be reconstructed from the compressed data. ... CorePNG is a lossless codec based on PNG. Essentially, each frame is compressed as a PNG, so if PNG does it, this codec does too. ... FFV1 which stands for FF video codec 1 is an experimental video encoder and decoder featuring lossless, intra-frame only and relatively high compression. ... Huffyuv (or HuffYUV) is a very fast, lossless Win32 video codec written by Ben Rudiak-Gould, meant to replace uncompressed YUV as a video capture format. ... Lagarith is an open source lossless video codec written by Ben Goldman. ... MSU Lossless video codec is an lossless video codec written by MSU Graphics&Media Lab Video Group. ...

Others

Cinepak · Dirac · Indeo · VP3 · VP7 · Pixlet · Snow · Tarkin · Theora · WMV Compressed with Cinepak, quality 40% Cinepak is a video codec, developed by Radius Inc to accommodate 1x (150 kbyte/s) CD-ROM transfer rates. ... Dirac is a prototype algorithm for the encoding and decoding (see codec) of raw video. ... Indeo Video (commonly known now simply as Indeo) is a video codec developed by Intel in 1992. ... VP3 was originally a proprietary video codec developed by On2 Technologies. ... TrueMotion VP7 is a video codec developed by On2 Technologies as a successor to earlier efforts such as VP3, VP5 and TrueMotion VP6. ... Pixlet is a video codec created by Apple Computer and based on wavelets, designed to enable viewing of full resolution, high resolution movies in real time at low DV data rates. ... Snow is an experimental video codec developed by Michael Niedermayer for the FFmpeg package. ... This page is about the video compression codec. ... Theora is a video codec being developed by the Xiph. ... Windows Media Video (WMV) is a generic name for the set of video codec technologies developed by Microsoft. ...

Audio codecs
(Comparison)

General

ADPCM · ATRAC · Dolby Digital · Musepack · TwinVQ · Vorbis · WMA An audio codec is a computer program that compresses/decompresses digital audio data according to a given audio file format or streaming audio format. ... The following tables compare general and technical information for a variety of audio codecs. ... Audio compression is a form of data compression designed to reduce the size of audio files. ... Pulse-code modulation (PCM) is a modulation technique. ... ATRAC (Adaptive TRansform Acoustic Coding) is a family of proprietary audio compression algorithms used to store information on MiniDiscs and other Sony-branded audio players. ... Musepack or MPC is an open source lossy audio codec, specifically optimized for transparent compression of stereo audio at bitrates of 160-180 kbit/s. ... TwinVQ (transform-domain weighted interleaved vector quantization) is an audio compression technique developed by Nippon Telegraph and Telephone Corporation (NTT). ... Vorbis is an open source, lossy audio codec project headed by the Xiph. ... Windows Media Audio (WMA) is a proprietary compressed audio file format developed by Microsoft. ...

Speech/Voice

iLBC · IMBE · iSAC · QCELP · Speex · Truespeech Speech coding is the compression of speech (into a code) for transmission with speech codecs that use audio signal processing and speech processing techniques. ... The Internet Low Bit Rate Codec (iLBC) is a royalty free narrowband speech codec, developed by Global IP Sound (GIPS). ... IMBE a is speech coding standard. ... iSAC is a wideband speech codec, developed by Global IP Sound (GIPS). ... QCELP is a speech codec developed in 1994 to increase the speech quality of the IS-96A codec used earlier in CDMA networks. ... Speex is a free software speech codec that claims to be unencumbered by patent restrictions. ... Truespeech is a proprietary audio codec produced by the DSP Group. ...

Lossless

Apple Lossless · Dolby TrueHD · FLAC · Monkey's Audio · TTA · WavPack · WMA Lossless Lossless data compression is a class of data compression algorithms that allows the exact original data to be reconstructed from the compressed data. ... Apple Lossless (also known as Apple Lossless Encoder, ALE, or Apple Lossless Audio Codec, ALAC) is an audio codec developed by Apple Inc. ... Dolby TrueHD logo Dolby TrueHD, from Dolby Laboratories, is an advanced lossless multi-channel audio codec, intended primarily for high-end home-entertainment equipment, such as Blu-ray Disc and HD DVD. In this application, Dolby TrueHD competes with DTS-HD Master Audio, another lossless codec from Digital Theater System. ... FLAC, an acronym for Free Lossless Audio Codec, is a popular file format for audio data compression. ... Monkeyâ€™s Audio is a lossless audio compression codec. ... True Audio (abbreviated TTA) is a free, simple real-time lossless audio codec, based on adaptive prognostic filters which has shown satisfactory results comparing to majority of modern analogs. ... WavPack is a free, open source lossless audio compression format developed by David Bryant. ... Windows Media Audio 9 Lossless is a lossless data lossless audio codec by Microsoft, released in early 2003. ...

Archivers
(Comparison)

Open Source

7-Zip · Ark · File Roller · KGB Archiver · PeaZip · The Unarchiver It has been suggested that this article or section be merged into Comparison of file archivers. ... The following tables compare general and technical information for a number of file archivers. ... Open source refers to projects that are open to the public and which draw on other projects that are freely available to the general public. ... 7-Zip is an open source file archiver designed originally for the Microsoft Windows operating system, and later made available to other systems. ... Ark is an archiving tool for KDE, included into kdeutils package. ... File-roller is an archive manager for the GNOME environment. ... KGB Archiver is an open-source file archiver and data compression utility created by Tomasz Pawlak. ... PeaZip is an open source OS-portable file archiver, released under LGPL for Microsoft Windows and Linux (Linux version requires libgdk_pixbuf library). ... The Unarchiver is an open source data compression utility, which supports more formats than BOMArchiveHelper, the built-in archive unpacker program in Mac OS X. It can also handle filenames in foreign character sets, created with non-English versions of other operating systems. ...

Freeware

DGCA · FilZip · GCA · IZArc · StuffIt Expander · TUGZip · Zipeg · ZipGenius · WinUHA This article or section does not cite any references or sources. ... In computing, DGCA is a freeware compression utility created in 2001 by Shin-ichi Tsuruta (鶴田真一, Shin-ichi Tsuruta). ... This article needs to be cleaned up to conform to a higher standard of quality. ... In computing, GCA is a freeware compression utility created in 2000 by Shin-ichi Tsuruta. ... IZArc is a freeware file archiver for Microsoft Windows. ... StuffIt Expander used to be a freeware, closed source data compression software utility developed by Allume Systems (formerly Aladdin Systems) It runs in Mac OS Classic, Mac OS X, Microsoft Windows, and Linux/UNIX. It does not compress files. ... TUGZip is a freeware file archiver for Microsoft Windows. ... Zipeg is a decompression application made by Leo Kuznetsov for Mac OS X that handles zip files. ... ZipGenius is a freeware file archiver designed for Microsoft Windows users, developed by Matteo Riso of M.Dev Software. ... UHarc is a solid, high-compression 386+ DOS and Windows file archiver with multimedia support. ...

Proprietary

ALZip · BOMArchiveHelper · MacBinary · PowerArchiver · Squeez · StuffIt · WinAce · WinRAR · WinRK · WinZip Proprietary software is software with restrictions on using, copying and modifying as enforced by the proprietor. ... ALZip is an archive and compression utility from ESTsoft for Microsoft Windows. ... BOMArchiveHelper is the default archive file handler in Mac OS X. It is a service application that has no GUI when double-clicked, rather it is invoked by opening its associated files or by choosing Create archive of file in the Finders contextual menu. ... Due to the Mac OS forked file structure, transferring Mac OS files to non-Macintosh computers is problematic. ... PowerArchiver is a proprietary file archiver designed for Microsoft Windows users, developed by ConeXware Inc. ... Squeez is a shareware file archiver and data compression utility by Speedproject. ... StuffIt is a family of software utilities for archiving and compressing files on the Apple Macintosh, Microsoft Windows and Linux platforms: it was originally produced for the Macintosh and remains common on that platform. ... WinAce is an archiving program with its own powerful ACE compression format and built-in support for other common archive formats types such as ZIP, RAR and MS-CAB. The Mac OS X and Linux versions are called Unace and are command line programs. ... WinRAR is a shareware file archiver and data compression utility by Eugene Roshal. ... WinRK is a commercial file archiver program for Microsoft Windows. ... WinZip Computing Inc. ...

Command line

ARC · ARJ · JAR · bzip2 · compress · gzip · Info-ZIP · LHA · lzop · NABOB · PAQ · PKZIP · RAR · SBC · UPX This article or section does not adequately cite its references or sources. ... ARC is a file format by SEA (System Enhancement Associates) that was very popular before Phil Katzs introduction of the ZIP format. ... ARJ is a tool for creating compressed file archives. ... JAR is a tool for creating compressed file archives. ... The correct title of this article is . ... Categories: Disambiguation | Software stubs | Data compression software ... The correct title of this article is . ... Info-ZIP is an open source version of Phil Katzs deflate and inflate routines used in his popular file compression program, PKZIP. The free code released by the Info-ZIP project under a BSD license spawned a horde of PKZIP imitators (WinZip, PicoZip, PowerArchiver, Turbozip, PowerZip and many more... LHA is a freeware compression utility and associated file format. ... LZOP is a free software file compression tool which uses LZO and is under the GPL license. ... NABOB was a joke file compression and archiving tool created by Thomas M. Tuerke (SysOp of Gravesend BBS) and Al Kalian (SysOp of Palladin BBS) at the height of the compression wars that resulted from the legal conflicts between ARC and Phil Katz. ... PAQ is a series of open source data compression archivers that have evolved through collaborative development to top rankings on several benchmarks measuring compression ratio (although at the expense of speed and memory usage). ... PKZIP is an archiving tool originally written by the late Phil Katz, and marketed by his company PKWARE, Inc. ... REDIRECT RAR (file format) ... SBC may refer to: Session Border Controller (VoIP, NGN term) // South Birmingham College, a college of Further Education in Birmingham, England St. ... UPX, the Ultimate Packer for eXecutables, is an open source executable packer (EXE packer) supporting a number of file formats. ...

(See Compression methods for methods and Compression formats and standards - for formats)

Contents

Versions GA_googleFillSlot("encyclopedia_square");

Dolby Digital

Dolby Digital EX

Dolby Digital Live

Dolby Digital Surround EX

Dolby Digital Plus

Dolby TrueHD

Channel configurations

Applications of Dolby Digital

Dolby Technologies in packaged media formats

See also

Technical details

References

External links

Versions