What Is Dolby Digital?

Dolby Digital was named as Dolby Studios until 1994.The first set of Dolby Digital was to provide digital sound in cinema hall from 35mm film prints.These systems are also used for the HDTV broadcasts

Dolby Digital is the version containing up to six discrete channels of sound and it is the most elaborate mode in common and uses five channels for normal range.

Dolby Digital uses audio coding and it reduces the amount of data needed to produce the high quality sound.The developers of of Dolby Digital includes the down mixing feature and that ensures the compatiblity with the device playback.It is used for film producers and consumers and its ability to use a single audio streaming video because of down mixture feature.The US cable televisions has also adopted the 5.1 channel sound and the 5.1 channel jas used primarily for theatrical movies.

Dolby has been enhanching since many decades and it is the true mother of all the surround sounds.Its encodes four analog audio channels into two channels and for storage and transmission or both and the device seperates the full four channels for play back. On February 17, 2005, the company became public, offering its shares on the New York Stock Exchange, under the symbol DLB. On March 15, 2005, Dolby celebrated its fortieth anniversary at the ShoWest 2005 Festival in San Francisco.On January 8, 2007, Dolby announced the arrival of Dolby Volume at the International Consumer Electronics Show. It enables users to maintain a steady volume while switching through channels or program elements (i.e., loud TV commercials)On June 18, 2010, Dolby introduced Dolby Surround 7.1, and set up theaters worldwide with 7.1 surround speaker setups to deliver theatrical 7.1 surround sound. 

The first film to be released with this format was Pixar's Toy Story 3 which was later followed by 50 releases using the format. As of April 2012, there are 3,600 Dolby Surround 7.1 movie theaters. In April 2012, Dolby introduced its Dolby Atmos, a new cinematic technology adding overhead sound, first applied in Pixar's motion picture Brave. In July 2014, Dolby Laboratories announced plans to bring Atmos to the home theatre industry.On February 24, 2014, Dolby acquired Doremi Labs for $92.5 million in cash plus an additional $20 million in contingent consideration that may be earned over a four-year period.

TECHNICAL DETAILS

Dolby's true HD sample rate is listed as being 96 khz and the frame rate of 12 per second seems implausible. Dolby and the double-D symbol are registered trademarks of Dolby Laboratories.Dolby digital was started in 1965 and it is the leading global developer of audio,imaging and voice technologies for home theaters, PC's mobile phones and games it has been elevating entertainment.Its home is in San Francisco,california and its been making media more real  more intense and more amazing and it made noise reduction and its been recently started with 3D imaging.You are actually a fan of Dolby digital since 45 years because it is the only thing that made home theatres,cinemas,computing etc. Dolby Digital provides five full bandwidth channels,front left,front right,center, surround left,and surround right,for true surround sound quality. A low frequency effect channel is included in it which provides the sound needed for special effects and action sequence in movies.

VERSIONS: Dolby digital has many versions which has similar technologies those are Dolby Digital EX, Dolby Digital Live,Dolby digital surround EX, Dolby Digital Recording,Dolby digital Cinema, Dolby Digital stereo creator and Dolby Digital creator

VERSION 1 - Dolby digital EX - this is a similar in practice to dolby's earlier pro logic format and it uses matrix technology and to add a center surround system channel. Dolby Digital EX adds an extension to standard 5.1 channel.

VERSION 2 - Dolby Digital surround EX - This is also called as an cinema version it developed by both Dolby and Lucas film and the episode of Star wars of 1999 May.The extra sound channel is matrix encoded onto the discrete left surround and right surround channels of 5.1 mix.The result can be played without loss of information on standard 5.1 systems or played in 6.1 or 7.1 on remastered original star wars trilogy.Many number of DVD's have the Dolby digital EX audio option.

VERSION 3 - Dolby digital live - It is an real time encoding technology for interactive media such as video games. It converts any audio signals on a PC or game console into a 5.1-channel 16-bit/48 kHz.There is an important benefit of this technology is that it enables the use of digital multichannel sound with consumer sound card,initially no creative X-Fi titanium series of sound cards which fully supports Dolby digital Live while leaving all PCI versions of creative X-fI still lacking support for DDL. Eventually Creative struck an agreement with Dolby Laboratories regarding the Dolby license royalty by arranging that the licensing cost be folded into the purchase price of the Creative X-Fi PCI cards rather than as a royalty paid by Creative themselves.

VERSION 4 - Dolby Digital Plus -The discontinue HD DVD system directly supported E-AC-3 blue ray disk offers E-AC as an option to graft added channels onto an otherwise 5.1 steam,as well for delivery of secondary audio content (e.g. director's commentary) that is intended to be mixed with the primary audio soundtrack in the Blu-ray Disc player.

VERSION 5 Dolby True HD - Dolby True HD, developed by Dolby Laboratories, is an advanced lossless audio codec based on Meridian Lossless Packing. Support for the codec was mandatory for HD DVD and is optional for Blu-ray Disc hardware.

APPLICATIONS - Dolby Digital audio is used on DVD-Video and other purely digital media, like home cinema.digital cable standards limit AC-3 to 448 kb/s. Blu-ray Disc, the PlayStation 3 and the Xbox game console can output an AC-3 signal at a full 640 kbit/s. Dolby is part of a group of organizations involved in the development of AAC (Advanced Audio Coding).

LICENSE - Patents are used to ask to pay a commercial license to publish an application that decodes AC3.This leads some audio app developers to ban AC3 from their apps.

ALTERNATIVES -  Other manufacturers have since produced standalone sound cars based on c-media which provides real time AC3 encoding comparable to sound storm or creative's audigy2 and later sound cars However, early versions of these alternatives may still be lagging behind the Sound Storm in terms of reliability, ease of use, and CPU usage.

HISTORY -

VIDEO GAME CONSOLES - Sound storm development was funded by microsoft for use in XBOX gaming console.A second generation chip has been developed,this time with funding from as part of PLAY STATION 3 project.

Discontinuation - Nvidia decided the cost of including the sound storm SIP block on the dies of three chipsets was too high and was not included in nForce3 and beyond.