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Timeline of audio formats
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codec examples
Following is a list of popular speech, audio and video codecs. A codec is the circuit that performs the conversion from analog to digital or digital to digital (see codec).
Speech is a Subset of Audio
Audio codecs cover all sound whether spoken words or music. However, in order to create the most compressed digital data, speech codecs look for sound patterns commonly heard in a spoken language.
SPEECH CODECS Name Purpose A-Law PCM telephony in Europe µ-Law PCM telephony in U.S. DV Audio MiniDV audio GSM 6.10 GSM cellphone G.711 A/V conferencing (ITU) G.722 A/V conferencing (ITU) G.723.1 VoIP, A/V conferencing (ITU) G.728 A/V conferencing (ITU) G.729 A/V conferencing (ITU) AMR-NB GSM, 3GPP (ETSI narrowband) AMR-WB GSM, 3GPP (ETSI wideband) ACELP.net General speech (VoiceAge) ACELP.wide High quality (VoiceAge) SOUNDTRACK CODECS Name Origin MP2 MPEG-2 Dolby Digital Dolby Labs DTS DTS, Inc. MUSIC CODECS Name Origin MP3 MPEG AAC MPEG AAC Protected MPEG with DRM WMA Windows WMA Protected Windows with DRM WMA Lossless Windows high quality RA, RAM RealNetworks AIFF Macintosh AU Sun ACELP.live VoiceAge Ogg Vorbis Open source high quality FLAC Open source high quality Apple Lossless High quality DSD High quality (SACD) DVD-Audio High quality VIDEOCONFERENCING CODECS Name Origin H.261 ITU H.263 ITU MOVIE CODECS Name Origin MPEG-1 Video CD MPEG-2 DVD/TV standard MPEG-4 Enhanced MPEG-2 H.264 Enhanced MPEG-4 FLV Flash video VC-1 SMPTE AVI Windows WMV Windows RM, RV RealNetworks Indeo Intel Cinepak SuperMac Technologies Sorenson Sorenson Media
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Timeline of audio formats
An audio format is a medium for storing sound and music. The term is applied to both the physical recording media and the recording formats of the audio content – in computer science it is often limited to the audio file format, but its wider use usually refers to the physical method used to store the data.
Music is recorded and distributed using a variety of audio formats, some of which store additional information.
Timeline of audio format developments
| Year | Media formats | Recording formats |
|---|---|---|
| 1877 | Phonograph cylinder | Mechanical analog; "hill-and-dale" grooves, vertical stylus motion |
| 1883 | Music roll | Mechanical digital (automated musical instruments) |
| 1895 | Gramophone record | Mechanical analog; lateral grooves, horizontal stylus motion |
| 1898 | Wire recording | Analog; magnetization; DC "bias" |
| 1925 | Electrical cut record | Mechanical analog; electrically cut from amplified microphone signal, lateral grooves, horizontal stylus motion, discs at 7", 10", 12", most at 78 rpm |
| 1930s | Reel-to-Reel, Magnetic Tape | Analog; magnetization; AC "bias" dramatically increases linearity/fidelity, tape speed at 30 ips, later 15 ips and other refined speeds: 7½ ips, 3¾ ips, 1⅞ ips |
| Electrical transcriptions | Mechanical analog; electrically cut from amplified microphone signal, high fidelity sound, lateral or vertical grooves, horizontal or vertical stylus motion, most discs 16" at 33⅓ rpm | |
| 1948 | Vinyl Record | Analog, with preemphasis and other equalization techniques (LP, RIAA); lateral grooves, horizontal stylus motion; discs at 7" (most 45 rpm), 10" and 12" (most 33⅓ rpm) |
| 1957 | Stereophonic Vinyl Record | Analog, with preemphasis and other equalization techniques. Combination lateral/vertical stylus motion with each channel encoded 45 degrees to the vertical. |
| 1962 | 4-Track (Stereo-Pak) | Analog, 1⁄4-inch-wide (6.4 mm) tape, 3¾ in/s, endless loop cartridge. |
| 1963 | Compact Cassette | Analog, with bias. 0.15-inch-wide (3.8 mm) tape, 1⅞ in/s. 1970: introduced Dolby noise reduction. |
| 1965 | 8-Track (Stereo-8) | Analog, ¼ inch wide tape, 3¾ in/s, endless loop cartridge. |
| 1969 | Microcassette | Analog, ⅛ inch wide tape, used generally for notetaking, mostly mono, some stereo (developed in the early 80's). 2.4 cm/s or 1.2 cm/s. |
| Minicassette | Analog, ⅛ inch wide tape, used generally for notetaking, 1.2 cm/s | |
| 1970 | Quadraphonic 8-Track (Quad-8) (Q8) | Analog, ¼ inch wide tape, 3¾ in/s, 4 Channel Stereo, endless loop cartridge. |
| 1971 | Quadraphonic Vinyl Record (CD-4) (SQ Matrix) | Analog. |
| 1975 | Betamax Digital Audio | Dolby Stereo cinema surround sound |
| 1976 | Elcaset | Analog. |
| 1978 | Laserdisc | Digital/Analog. |
| 1982 | Compact Disc (CD-DA) | Digital. PCM |
| 1985 | Audio Interchange File Format (AIFF) | |
| 1985 | Sound Designer (by Digidesign) | |
| 1986 | High Definition Compatible Digital (HDCD) | Digital. Redbook compatible physical CD containing 20–24 bit information. |
| 1987 | Digital Audio Tape (DAT) | Digital. |
| 1991 | MiniDisc (MD) | Digital. Adaptive Transform Acoustic Coding (ATRAC) |
| 1992 | Digital Compact Cassette (DCC) | Digital. |
| WAVEform (WAV)
Dolby Digital surround cinema sound |
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| 1993 | Digital Theatre System (DTS) | |
| 1997 | DVD | Dolby Digital, Digital Theatre System (DTS) |
| DTS-CD | DTS Audio | |
| 1999 | DVD-Audio | Digital. |
| Super Audio CD (SACD) | Direct Stream Digital | |
| Windows Media Audio (WMA) | ||
| The True Audio Lossless Codec (TTA) | ||
| 2000 | Free Lossless Audio Codec (FLAC) | |
| 2001 | Advanced audio coding (AAC) | |
| 2002 | Ogg Vorbis | |
| 2003 | DualDisc | Digital. |
| 2004 | Apple Lossless (ALE or ALAC) | |
| 2005 | HD DVD | Dolby TrueHD, DTS-HD Master Audio |
| OggPCM | ||
| 2006 | Blu-ray Disc | Dolby TrueHD, DTS-HD Master Audio |
| 2008 | slotMusic | Usually at 320kbit/s MP3 on microSD or microSDHC |
| Blu-spec CD | Digital. PCM |
See also
External links
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