DTS 5.1 transcoding in Gotham Beta
#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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#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 (wiki) 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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#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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#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 (wiki) 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 (wiki) 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.
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#20
(2014-08-21, 11:40)jjd-uk Wrote: Guess you didn't read the wiki Audio_settings (wiki) 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 (wiki) 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.

Actually, I'm using Openelec as the base for that XBMC install. I found this post with a search trying to troubleshoot the issue.

Reading your post, the way you explain it, yes it makes sense. I would still insist however that it is counter-intuitive. No other appliance requests you to specify the number of channels, vs the number of speakers. It may be how it technically works, but it's unfortunately not the common way people are used to setting up the audio in their devices.

If you have 5.1 speakers, desire surround sound, and still end up with only 2.0 output, that is as wrong a setting as any other combination that doesn't work.

Intuitive setup is one that does not require you to read pages of user manuals (i.e. wiki) to use something (particularly a product like XBMC that I've been using since ~2005). You say that I'm making a common mistake, I say that I am simply expecting 'Kodi' to behave like every other product I use. I read what you are saying, and I hear Steve Jobs telling his users they are holding their phones wrong. Get what I'm saying? Instead of trying to make the setup more technically correct, make it easier to find right combinations of settings user wants -- user focused. I can't imagine that the typical user knows how many PCM channels they have available, or understand it's relationship to getting correct output; that is unclear. How many speakers you have, however, is pretty obvious to every user and should be the base setting a user has access to.

If you're dead set on doing it this way, an Audio Config wizard to help find the right settings may be worth the trouble. Otherwise, as a loyal user, I would simply suggest that it would be less confusing to users to have a setting that specifically defines the number of speakers in use, and expose PCM channel settings only if the speaker count goes over 2.0. It makes infinitely more sense to me, to start with telling Kodi definitely how many speakers I have, then Kodi shows me what settings I need to look at to make this work. More accessible, not more complicated.

Although I suspect what I'm saying is falling on deaf ears, I'm saying it anyway. Undecided
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#21
Not on deaf ears at all, we've considered all the points you raised when reworking the audio settings.

What you say about consumer appliances maybe correct, however every PC OS out there refers to audio in terms of channels where those are PCM channels for the connection and not the number of speakers, so it's certainly a common way of settings up audio on PC's. However we recognise for the less techie it can take a mental leap to understand the 5.1 audio can be sent over 2.0 channels, hence we've tried to make the setting descriptions as clear as possible and explain things better on the wiki.

What you suggest by specifying the actual number of physical speakers would just not work as we need to know when Multichannel PCM is and is not possible, since the Transcode to Dolby Digital option only makes sense when Multichannel PCM is not available.

The only possible solution I see is for XBMC to automatically set the number of channels based on what the driver reports, however this also has pitfalls in that the info that is used to generate this can sometimes be wrong, so we would still need to retain a manual settings to allow the setting to be overridden. However auto setup like this would not be possible on all platforms XBMC supports so you would lose consistency between the different builds of XBMC for each platform.

I'm certainly open to ideas & suggestions on improvements, and if there's a case that can be made then I'll certainly push for it within the Team to try and make change happen.
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#22
(2014-03-19, 23:33)sialivi Wrote:
(2014-03-19, 23:24)buhohitr Wrote: Where id you get all these settings from?? I'm using Gotham beta2 and I don't have the following settings:
AC3 capable receiver" on
" - Enable Dolby Digital transcoding" on
"DTS capable receiver" off

You need to change the "Settings level" to Advanced or Expert. The option is in the bottom left corner.

Hi,
I'm having the same issue with sound coming out the wrong speakers. Switching on/off hdmi audio fixes it but not permanently. So had a look for a solution and came across this.

Trouble I am having is that I really can't find the settings level? Nothing bottom left as indicated. I'm using Aeon nox skin if that makes a difference.

thanks
el-d

Scrap that.. too much wine Wink ... switch to Confluence and settings will be there Smile
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DTS 5.1 transcoding in Gotham Beta0