DTS Coherent Acoustics is the full name for the audio format standard usually known as just DTS. It is covered in U.S. Patent 5,956,674 . DTS (formerly known as Digital Theater Systems), owned by DTS, Inc. ...

Overview

DTS can transport audio up to 8 audio channels at up to a 192kHz sampling rate. It can be transported over S/PDIF, or can be encapsulated in wave files, DVDs and stored on CDDAs. DTS codecs exist for desktop computers as well as being embedded into many home cinema AV receivers. The format offers variable compression ratios, targeting a wide variety of bit rates, although the most often used compression ratio for DVD and cinema audio is about 1:4, resulting in a fairly high bitrate. DTS also includes several low-bitrate hacks, such as joint frequency encoding, that are generally frowned upon in this context, and should not be encountered on high quality DTS source material. The sampling frequency or sampling rate defines the number of samples per second taken from a continuous signal to make a discrete signal. ... S/PDIF or S/P-DIF stands for Sony/Philips Digital Interface Format, also IEC 958 type II, part of IEC-60958. ... 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. ... Rainbow Books: Red Book (CD Digital Audio), Yellow Book (CD-ROM and CD-ROM XA), Orange Book (CD_R and CD-RW), White Book (Video CD), Blue Book (Enhanced Music CD, CD+G and CD-Plus), Beige Book (Photo CD), Green Book (CD-i). ... A codec is a device or program capable of performing encoding and decoding on a digital data stream or signal. ... A 3 metres/119 inch projection screen with a high-definition television image. ... In telecommunications and computing, bitrate (sometimes written bit rate, data rate or as a variable Rbit) is the number of bits that are conveyed or processed per unit of time. ... Look up hack, hacking in Wiktionary, the free dictionary. ... In audio engineering, joint refers to a joining of several channels of similar information in some way, in order to obtain, for example, higher quality or smaller file size. ...

The base specification allows for 5.1 channels of audio with a 48kHz sampling rate. Further specification extensions allow for an additional 2 channels and/or additional high frequency data to be transmitted. It encodes audio by splitting it into 32 subbands, each with a bandwidth of 750 Hz, which are then encoded using ADPCM. There are 4 ADPCM coefficients, which are processed with vector quantization for transmission (there is a 4,096-entry codebook). The residual (prediction error) is quantized either linearly (using a variable number of bits), or using VQ, depending on the bit allocation to the subband - a global bit allocation scheme allocates bits to each subband. Data bits may also be entropy encoded. The sampling frequency or sampling rate defines the number of samples per second taken from a continuous signal to make a discrete signal. ... This article or section does not cite its references or sources. ... The hertz (symbol: Hz) is the SI unit of frequency. ... Pulse-code modulation (PCM) is a modulation technique. ... In mathematics, a coefficient is a constant multiplicative factor of a certain object. ... In data compression, vector quantization is a quantization technique often used in lossy data compression in which the basic idea is to code or replace with a key, values from a multidimensional vector space into values from a discrete subspace of lower dimension. ... An entropy encoding is a coding scheme that assigns codes to symbols so as to match code lengths with the probabilities of the symbols. ...

Due to less calculations involved in higher bitrates, DTS encoding is particularly fast and CPU-easy compared to Dolby Digital. Real-time DTS encoding is also inherently low-latency compared to the 130ms of Dolby Digital, making it much more suitable for interactive (real-time) applications, such as video games. Several Playstation 2 games have offered DTS 5.1 surround output, in addition to stereo Pro-logic encoded PCM. DTS 5.1 output is also offered on several models of HD DVD players, where the player converts an original soundtrack (of Dolby Digital +, Dolby True-HD, or multi-channel LPCM) into a DTS 5.1 bitstream. Wikipedia does not have an article with this exact name. ... 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...

Theatrical DTS and consumer (home-theater) DTS are not the same codec. Home-theater receivers cannot be used with theatrical DTS programming, and vice versa.

The DTS Coherent Acoustics standard (ETSI 102 114 v1.2.1), is published by the ETSI and available at[1] (look for DTS Coherent Acoustics). The European Telecommunications Standards Institute (ETSI) is a standardization organization of the telecommunications industry (equipment makers and network operators) in Europe, with worldwide projection. ...

DTS in Cinemas (Film)

DTS is used on film prints, where it competes with the Dolby Digital (AC-3) and SDDS standards. It is used less often than Dolby Digital. Dolby Digital and SDDS tracks are printed onto the physical film medium, as their bit-rates allows them to fit in limited space. A DTS track however has a higher bitrate and therefore cannot be printed onto the film. Instead a timecode is printed onto the film and the DTS soundtrack shipped to the cinema as a pair of CDs in addition to the film reels. When the film is projected, the timecode is read from the film and the equivalent sound comes from the DTS CD-decoding equipment.

It is argued that in a cinema environment DTS produces higher-fidelity sound than DD encoded film, and greater robustness in the event of damaged film, but the extra complication of using CDs is less convenient for the projectionist and they are more likely to be missing or damaged.

See also

• Home cinema
• Codec
• Dolby Digital
• libdca