Dolby Digital Plus

from Wikipedia, the free encyclopedia
The Dolby Digital Plus logo

Dolby Digital Plus (DD +) is a multi-channel sound system from Dolby and was first presented to the German trade press at the end of October 2005. It was specially developed for use in high-definition television HDTV , the DVD successor formats HD DVD and Blu-ray Disc , as well as for encoding multi-channel media for streaming , on-demand and download services that could only output uncoded stereo sound , see above z. B. for the paid streaming service Microsoft Azure Media Services. Dolby Digital Plus is also used for psychoacoustic room simulation ( Surround Virtualizer ), to improve speech intelligibility ( Dialogue Enhancer ) and for acoustic dynamic compression ( Volume Leveler ) of stereo and multi-channel sound for playback with headphones on mobile devices such as tablets and smartphones with Android - and Windows Mobile operating system. A selection menu is available for the different music genres . Thus Dolby Digital Plus is in competition with the psychoacoustic concept SRS of SRS Labs, Inc. which since 2012 under the brand name Headphone: X of DTS , Inc. will continue.

The Dolby Digital Plus Codec supports data rates up to 6 Mbit / s (DVD: 448 kbit / s) and up to 7.1 channels. DD + is the successor to Dolby Digital, which is widely used primarily on DVD . Support for the Dolby Digital Plus codec is optional for Blu-ray players. This is why the Dolby Digital Plus variant common on Blu-ray discs usually contains a backward-compatible core that is compressed using the conventional Dolby Digital method ( 5.1 channels). Depending on the capabilities of the other playback components, the user can select in the settings of the BD player whether the complete Dolby Digital Plus signal or only the downward compatible core should be used. In contrast to this, the HD-DVD standard, which is no longer being pursued, required the support of Dolby Digital Plus by the player to be mandatory . The variant of DD + used on HD-DVD was not backwards compatible with the older Dolby Digital. For this reason, an HD-DVD player had to be able to decode a Dolby Digital Plus sound track itself and also to convert a DD + sound track into a conventional Dolby Digital signal in real time.

specification

  • Data rate: 32 to 6,144 kbit / s
  • Channels: 8 (7.1) channels
  • Sampling rate: 48 or 96 kHz
  • Bit depth: up to 24 bits
  • Compatibility: with Dolby Digital and with Dolby Pro Logic

transmission

Unchanged digital transmission of DD + (official abbreviation: E-AC-3) is currently only provided via HDMI . Due to the insufficient bandwidth of the S / PDIF interface, a real-time conversion of approx. 6 Mbit / s to lower data rates is carried out with DD + so that the S / PDIF and TOSLINK interface can also output a signal.

Further use

Dolby Digital Plus was used as the primary audio option on the HD DVD . Today DD + appears in a “slimmed-down” form on Blu-ray discs , and it is also shown on all SimpliTV (DVB-T2) channels in Austria / Servus TV (DVB-S2) in Austria and Germany as well as some French terrestrial TV channels TNT (a kind of extended DVB-T ) is broadcast. In addition, DD + is output from the Amazon video service Amazon Video using the Fire TV streaming device via HDMI.

Single receipts

  1. ↑ Transmission problems - Dolby corrects information on Dolby Digital Plus and TrueHD - on heise.de, accessed on July 7, 2015.
  2. ↑ What is Dolby Digital Plus? - from audiogurus.com, accessed July 7, 2015.
  3. ↑ Encoding your media with Dolby Digital Plus - from azure.microsoft.com, accessed July 7, 2015
  4. ↑ Dolby Digital Plus - from dolby.com, accessed July 7, 2015
  5. ↑ Dolby Digital Plus for Android One Smartphones - from informationlord.com, accessed July 7, 2015
  6. ↑ Ignite Windows with Dolby Audio ( Memento of the original from July 7, 2015 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. - from developer.dolby.com, accessed July 7, 2015. @1@ 2Template: Webachiv / IABot / developer.dolby.com
  7. ↑ Dolby Digital Plus: Sound improvement for tablets presented - at www.giga.de, accessed on July 7, 2015.
  8. ↑ DTS: X multi-dimensional sound - on dts.com, English, accessed on July 7, 2015.
  9. ↑ French, terrestrial TNT aerial television service with HD channels and, for the first time, Dolby Digital Plus ( Memento from November 11, 2010 in the Internet Archive ) - on archive.is

Web links