DTS 5.1 transcoding in Gotham Beta

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dml3334 Offline
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Post: #16
Thank you very much for the explanation, jjd-uk. I was completly wrong. I thought AAC -> AC3 transcoding was quite more direct and simple.

Could an explanation like this be inserted in the Wiki? In many occasions, there are so many options, so many possibilities and the Wiki too short that you can get misunderstood very easily.

Thanks again.
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jjd-uk Online
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Post: #17
I've been helping to improve the information on audio on the wiki pages, I made a start on explaining some of the concepts at Audio_troubleshooting however I've not had much time recently so it's still a work in progress. When I've time I'll look into expanding the transcoding explanation and maybe that whole Background section should be split off into it's own page.
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DarkKnight Offline
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Post: #18
(2014-03-11 12:03)jjd-uk Wrote:  It doesn't show because there's a dependency on only 2 channels being available as that is the normal use case.

It most common usage is sending multichannel 5.1 over SPDIF to an AVR where you've only got 2.0 PCM channels available.

For HDMI you either connected to an AVR where 5.1 PCM or greater channels is available so it's best to decode to 5.1 PCM in order to keep the original quality, or to a TV which where again the transcode option it might be useful because only 2.0 PCM is available.

The setting system for audio has been redesigned to only present options where it makes sense to show them, thus various things will appear and disappear depending on what's selected.

I'd just like to put my $.02 that this is extremely counter intuitive. Burying an option, completely unexplained, behind a specific combination of settings is silly. Why would anyone think to set their speakers to 2.0, when they have & need 5.1, only then to get the option to encode it at 5.1....? It took me over an hour screwing with it before I found the post above yours explaining it.

In my case, my AVR doesn't switch HDMI, so to keep from having to switch the input on both the TV & the AVR, I feed the audio through the TV and let the TV pass 5.1 back to the AVR from whatever input I have the TV set to. This passes 5.1 natively with my Cable STB & Gaming PC without needing to play sherlock about where options for it are hiding. I'm glad the new audio engine in XBMC/Kodi allows this, but seriously, you should reconsider how dumbed down you are going for with the interface.
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jjd-uk Online
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Post: #19
(2014-08-21 04:26)DarkKnight Wrote:  I'd just like to put my $.02 that this is extremely counter intuitive. Burying an option, completely unexplained, behind a specific combination of settings is silly. Why would anyone think to set their speakers to 2.0, when they have & need 5.1, only then to get the option to encode it at 5.1....? It took me over an hour screwing with it before I found the post above yours explaining it.

In my case, my AVR doesn't switch HDMI, so to keep from having to switch the input on both the TV & the AVR, I feed the audio through the TV and let the TV pass 5.1 back to the AVR from whatever input I have the TV set to. This passes 5.1 natively with my Cable STB & Gaming PC without needing to play sherlock about where options for it are hiding. I'm glad the new audio engine in XBMC/Kodi allows this, but seriously, you should reconsider how dumbed down you are going for with the interface.

Guess you didn't read the wiki Audio_settings then?

You seem to have a common misunderstanding on how audio works, this is why Speaker Configuration was renamed Number of Channels as this setting has nothing to do with the number of physical speakers you have. What this setting does is tell XBMC the number of PCM channels a connection supports, this is why it's been removed for SPDIF as this only supports 2.0 PCM channels, where PCM channels is an expression of the raw bandwidth.

Dolby Digital for example is an compressed format which fits within a link that only supports 2 PCM channels, a bit more detail at Audio_troubleshooting hence DD5.1 can pass over a PCM 2.0 link.

Since this post is in the Windows area I'm guessing you're actually have Windows as your OS, if you look at the audio properties you should find Max Number of Channels for your HDMI device, since you're connected to a TV this will almost certainly be 2 hence XBMC must also be set to 2 for Number of Channels, this is another reason for the change of language from Speaker Configuration to nudge the user that Max Number of Channels in Windows and Number of Channels in XBMC are related.

With the new settings in Gotham we try to only expose valid options depending on selected options to keep wrong settings to a minimum, so with HDMI if Number of Channels 5.1 is selected then Transcode option is hidden as it's only relevant when 2.0 is selected, hence selecting 5.1 in your case would have been totally wrong.
(This post was last modified: 2014-08-21 11:42 by jjd-uk.)
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