Quote:
Originally Posted by jdobbs
It is reencoded to AC3 so you need Directshow to decode.
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Ah, not good as I want the EAC3/DD+ to be passed through untouched. If I wanted it re-encoded, I'd do that myself. The less Dolby Digital recoding the better the audio quality.
Quote:
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E-AC3 & DD+ are illegal in BD if they don't have a AC3 core included (if memory serves me correctly).
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Digging thru my Bluray Demystified book (going to the indexed pages about DD+) I found the following:
a) first a note about DD+ in the table for Blu-ray audio formats:
Code:
Dolby Digital Plus is only supported for more than 5.1 channels. The initial 5.1 channels
are encoded with the core Dolby Digital Substream - channel 7 and 8 (if available) are
encoded in Dolby Digital Plus.
b) In the body of the section:
Code:
Dolby Digital Plus (DD+) is an extension of the legacy Dolby Digital format and provides
two additional channels, up to 7.1 channels. DD+ is based on the core Dolby Digital stream
and only the additional two channels are encoded using the DD+ extension while the core
5.1 streams are still encoded with the legacy Dolby Digital Substream.
So, why is services like Netfix and Amazon doing DD+ audio, but only providing 5.1 channels? Good question. Amazon is rolling it out more. Plus, how are DD+ encoders, like ffmpeg, able to flag an AC3 file as EAC3 with only 5.1 channels? No idea. I'd have to ask the ffmpeg coders that.
But, I found the free Dolby technical paper:
https://www.dolby.com/us/en/technolo...tech-paper.pdf
What is interesting with this paper is that the 5.1 core can only be a max of 640 kbps.
So, based upon what I have read, the DD+ stream can be passed along untouched. In the case of DD+ having 7.1 channels, it MUST be passed though untouched. But, in order to allow for recoding to AC3 5.1, adding a hidden flag (DDPlus_recode=1, where 1 is the default and changing it to 0 allows for pass-through, no matter what).