Audio Processing in Blu-ray Disc Players

The most practical way Blu-ray Disc™ players implement the BonusView and BD-Live™ interactive features is by processing all of the related audio elements in the player. This is the same processing model that has been used for video on DVDs: the main video is decoded, then overlaid with subtitles or menus, and output as a complete video presentation, either as analog (composite, component) or digital (DVI, HDMI™) baseband signals.

In a Blu-ray Disc player, soundtracks decoded from the disc, as well as audio elements streamed or downloaded from an Internet connection or generated internally in the player, are decoded as digital PCM signals. PCM is the format players use to perform all internal audio processing operations, including mixing. In the mixing stage, secondary audio, button sounds, streaming commentary, and other non-disc-audio are mixed with the primary 5.1 or 7.1 soundtrack from the disc. The result is the complete audio presentation as intended by the content creator.

The built-in decoding of these high-definition formats enables full playback compatibility with next-generation A/V receivers as well as earlier A/V receivers not equipped with Dolby Digital Plus and Dolby TrueHD decoders.

Depending on the model, Blu-ray Disc players can output internally decoded soundtracks as follows:

  • As a multichannel PCM signal via HDMI
  • As a multichannel analog signal via analog connections
  • As a Dolby Digital signal via a coaxial or digital connection*

Many Blu-ray Disc players offer the choice of all three.

HDMI can transport both digital audio and video signals, so you need only one cable connecting your player and A/V receiver. In addition, connection via HDMI may enable the full application of your A/V receiver’s DSP postprocessing features, such as bass management, the 5.1- to 7.1- to 9.1-channel expansion capability of Dolby Pro Logic® IIx or Dolby Pro Logic IIz, and speaker distance settings.

Multichannel analog outputs let you enjoy full high-definition audio from a Blu-ray Disc player connected to an A/V receiver equipped with multichannel analog inputs. However, some receivers do not apply DSP postprocessing to analog input signals. If your receiver does not, you should choose a Blu-ray Disc player that provides bass management, which is particularly important if you have a subwoofer/satellite speaker system.

The coaxial or optical digital audio output enables 5.1-channel playback through A/V receivers and home-theater-in-a-box (HTIB) systems equipped only with Dolby Digital decoding*. While you won’t realize the full high-definition capabilities of Dolby Digital Plus and Dolby TrueHD soundtracks, the sound quality can be better than that of standard-definition DVD, because your Dolby Digital receiver can take advantage of a higher 640 kbps core Dolby Digital signal on Blu-ray™ discs.

*The player requires a Dolby Digital Compatible Output feature to enable the output of decoded Dolby TrueHD signals as a 640 kbps Dolby Digital bitstream.

Note: Each of these options, as well as HDMI 1.3, let you enjoy the new interactive features on Blu-ray Disc players equipped with BonusView and/or BD-Live.


A/V Receivers with Dolby Digital Plus and Dolby TrueHD Decoding

Advanced A/V receivers feature HDMI 1.3 inputs and built-in Dolby Digital Plus and Dolby TrueHD decoders. This enables the receiver to decode high-definition theatrical (primary) soundtracks transported in their native format directly from Blu-ray Disc players equipped with HDMI 1.3 and bitstream out capability.

HDMI 1.3 provides all the standard HDMI benefits, including a single-cable connection for both audio (bitstream and PCM) and video as well as the proper application of the receiver’s DSP postprocessing, including bass management.

In addition, decoding theatrical soundtracks in your A/V receiver can enable full 96/24 digital audio capability when it is not supported in the player. Your system will also be ready for Dolby Digital Plus and Dolby TrueHD signals from future set-top boxes, Internet audio and video sources, and downloadable HD media devices.