what is teh ifference btween DTS,Dolby digital,ac3 etc

[dittualex]

hi,
iw ant to know the differnece btween DTSand dolby digital

[ishaan]

DTS - http://en.wikipedia.org/wiki/Digital_Theatre_System


DOLBY - http://en.wikipedia.org/wiki/Dolby

incase ur wondering which one u should choose wile seeing a movie, it depends

if u got 5.1 surrond take DTS if u got 2.1 take dolby

(unless it says dolby5.1 then u can take that also both will be as good)

(most prob its 5.1 if u got surrond)
if u got no surround system then it doesnt really matter that much what u choose

AC3 - http://en.wikipedia.org/wiki/AC3

[Keith Sebastian]

Originally Posted by ishaan

incase ur wondering which one u should choose wile seeing a movie, it depends

if u got 5.1 surrond take DTS if u got 2.1 take dolby

This has nothing to do with 5.1 or 2.1 or whatever.

Both DTS and DD 5.1 (Dolby Digital) are audio encoding formats. DD uses AC3 codec for encoding.

Not all Hollywood DVD movies have audio in both DTS and DD 5.1. So your comment isn't right. Selection of audio should be done based on what is available on the DVD, what your DVD player is capable of decoding and what your home theatre reciever is capable of decoding. All three factors are critical.

Hope I've made myself clear.

Also, most commercially available DVD's have only DD5.1 for the main movie (and mpeg1 layer2 stereo for commentaries and extras).

Some have selectable audio, both DTS and DD5.1

DTS was introduced by Steven Spielbergs Dreamworks studios, first featured in Jurassic Park. As DTS audio is much less compressed, video bitrate is reduced to stay within total bitrate limits of DVD.

Keith

[dreams]

Ya actually DTS, Dolby Digital and AC3 are nothin but Audio Encoding techniques.. to learn more abt these tech u can go to google search and can get many useful sites..

i personally searched and got some new techies.. now goin deep in it..

Some samples..

Dolby Digital

A digital audio encoding system from Dolby used in movie and home theaters. First used in 1995, Dolby Digital employs Dolby's AC-3 (Audio Coding-3) coding and compression technology and is the standard for DVD-Video and HDTV.

5.1 Channels

Dolby Digital provides five discrete channels of audio plus a subwoofer channel for low frequency effects (the "1" in the 5.1). The five channels are front left, right and center and surround left and right.

6.1 Channels

Co-developed with Lucasfilm THX, Dolby Digital Surround EX adds a center surround channel. The first film to use this enhanced version of Dolby Digital was "Star Wars: Episode I - The Phantom Menace," in 1999.

Dolby Digital is the trademarked marketing name for Dolby Laboratories' 'lossy' AC-3 codec. The common version contains 5.1 channels (five primary speakers and an LFE channel), but the format supports Mono and Stereo usages as well.

Dolby Digital EX is very 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 a 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 like the competing DTS-ES codec.

Dolby Digital Surround EX: Whereas Dolby's Pro-Logic IIx format creates 6.1 and 7.1 channel output from stereo 2 channel (2.0). Dolby formats, the Digital Surround EX codec adds a sixth and sometimes seventh channel to standard (non-EX) 5.1 channel Dolby Digital soundtracks.

Dolby Digital Plus is an enhanced coding system based on the AC-3 codec. It offers increased bitrates (up to 3 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.

Alias names
Dolby Digital (promotion name, not accepted by the ATSC), often combined with channel count (DD 5.1)
DD (an abbreviation of above)
Dolby SR-Digital (when the recording incorporates a Dolby Surround-format recording for compatibility)
SR-D (an abbreviation of above)
Adaptive Transform Coder 3 (relates to the bitstream format of Dolby Digital)
AC-3 (an abbreviation of above)
Audio Codec 3, Advanced Codec 3, Acoustic Coder 3 (These are backronyms. However, Adaptive Transform Acoustic Coding 3, or ATRAC3, is a separate format developed by Sony)
ATSC A/52 (name of the standard, current version is A/52 Rev. A)

These are all different names for the same codec.

Applications of Dolby Digital

Dolby Digital SR-D cinema soundtracks are optically recorded on a 35mm 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.

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 system is used in many bandwidth-limited applications other than DVD Video, such as digital TV.

According to the AC-3 standard, the maximum bit rate is 640 kbit/s. DVD-Video limits AC-3 to 448 kbit/s. Digital cable TV standards limit AC-3 to 448 kbit/s. ATSC limits AC-3 to 384 kbit/s.

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.

Dolby Digital Plus (DD-Plus) will likely be deployed in future-generation DVD standards. As of May 2005, DD-Plus is a "mandatory codec" for HD-DVD. This means all HD-DVD hardware will be capable of decoding audio-content compressed by DD-Plus. DD-Plus is also an "optional codec" for Blu-ray Disc.

DTS

(Digital Theatre Sound) A digital audio encoding system used in movie and home theaters. Popularized by the movie Jurassic Park, the soundtrack is maintained on CD-ROMs that are synchronized with the DTS timecode in the film, making it compatible with existing theater systems. The conventional stereo optical audio track is still on film for backup.

For Home Theaters

DTS Digital Surround is the home theater counterpart, and many DVD players support DTS 5.1 channel and DTS ES (Extended Surround) 6.1 channel. DTS is the least compressed digital audio format, and many claim it to be the best quality. See Dolby Digital, SDDS and THX.

AC-3

(Active Coding-3) Dolby's third digital audio coding technology based on a perceptual coding method. It is more advanced than AC-2 and provides six channels of audio in less space than two-channel stereo CD. AC-3 and "Dolby Digital" are synonymous.