transport stream. The AES stream can contain non-audio data as well as uncompressed audio. This mechanism can be used to
carry Linear PCM audio, or Dolby E data.
Dolby E
Dolby E was developed by Dolby Laboratories. It allows up to 8 channels of Dolby E compressed audio to be distributed over an
existing 2 channel digital infrastructure. The compression applied is less than that for consumer codecs (i.e. Dolby Digital), so is
better quality and the audio can be decompressed and re-compressed several times. The Dolby E stream can also include metadata
and timecode.
Dolby E frame duration is either equal to or double the duration of a video frame. For interlaced formats the duration matches a
video frame, but is double the frame duration for progressive formats. This facilitates easier editing of video and audio in the digital
domain. Dolby E frames are generally aligned to video frames.
Dolby E PCM Bypass and Switchout
Audio routing for PCM bypass and switchout when Dolby E is not present on the main input is shown in the diagrams below.
© Ericsson AB 2011. All rights reserved
© Ericsson AB 2011. All rights reserved
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