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Adjust bitrate for transcoded audio such as Dolby AC-3

transcoding dolby ac-3 bitrate embyserver

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#21 Jdiesel OFFLINE  

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Posted 09 January 2020 - 03:02 PM

Everything that I've seen shows that AC3 5.1 640Kb/s won't work.

 

Try one of the trailers from here

 

https://thedigitalth...dolby-trailers/



#22 Doofus OFFLINE  

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Posted 09 January 2020 - 03:09 PM

I don't need trailers. I can make audio do whatever I want. Unfortunately, I don't have a 20ft optical cable, presently. I'll confess, I haven't actually tested this in a while. It might be interesting to acquire a long cable, and put it through its paces.

#23 Doofus OFFLINE  

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Posted 09 January 2020 - 03:54 PM

Come to think of it, I'm not sure I have any devices with an optical output. My mini PC might...

Damn! It doesn't.

Edited by Doofus, 09 January 2020 - 04:57 PM.


#24 Charlie117 OFFLINE  

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Posted 09 January 2020 - 06:28 PM

S/PDIF isn't specific to optical, it's just the protocol. Example. mpv uses S/PDIF for all audio bitstreaming. In the log, the audio is always shown as S/PDIF stereo, but the audio details show it as 6 channel. We are talking about the physical entity of the fiber optic cable. It doesn't have the bandwidth, never has. Unless you can produce a log from the recipient end of the cable that shows 5.1 at 640Kb/s being decoded to raw audio, it isn't happening.

 

Admittedly, I am mixing up terms here. But this is really not any useful contribution from your end.

 

You are the sole person here claiming something that is very controversial and unsupported except for some graphic featured in a  What HiFi article that isn't even discussed or mentioned again for the rest of the article. Numerous sources, including Dolby Laboratories themselves, confirm that 640 kbps is very much possible over the mentioned connection.

 

Now, instead of you proving your controversial statement, which would be common sense, I am offering to disprove it by confirming what has already been established as fact. To do that, I am asking your help in obtaining the device playback logs you are requesting, because I do not know how to retrieve them.

 

Also, this Wikipedia article about Toslink appears to directly contradicts your statement that "It doesn't have the bandwidth, never has" 

https://en.wikipedia.org/wiki/TOSLINK

Screenshot-2020-01-09-at-23-30-59.png

 

 

Unless you can produce a log from the recipient end of the cable that shows 5.1 at 640Kb/s being decoded to raw audio, it isn't happening.

 

Unless you are able to prove otherwise, it is most definitely happening. It is an established fact. DVDs have been using DD 5.1 448 kbps bitrate audio for more than a decade and several streaming services, including Netflix and Amazon Prime, are sending DD 5.1 640 kbps audio to their clients. You would expect a ton more issues with 640 kbps DD 5.1 if it wasn't 100% supported as it is.


Edited by Charlie117, 09 January 2020 - 06:37 PM.


#25 Doofus OFFLINE  

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Posted 09 January 2020 - 06:38 PM

Ok, I'm the sole person 🙄

I don't believe it.

This is still a bad idea 👎 -1 and all that silliness

#26 Charlie117 OFFLINE  

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Posted 09 January 2020 - 06:42 PM

Ok, I'm the sole person

 

Who else in this thread is supporting your controversial opinion then? Please do quote them.

 

It's great that you were able to help certain users on this forum with issues that were resolved by forcing a transcode to AC-3 384 kbps. But that doesn't mean 640 kbps isn't generally supported.

 

Calling this suggestion a bad idea just because you were proven wrong is seriously petty though.


Edited by Charlie117, 09 January 2020 - 06:46 PM.


#27 Doofus OFFLINE  

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Posted 09 January 2020 - 07:00 PM

I'm not wrong. Less and less devices have an optical port. It's an antiquated standard. Just because at the pinnacle, it's possible, how many manufacturers will actually invest in the later standards when HDMI is ubiquitous? Very few. So what that means is that most optical solutions provided in the real world, will be crap. Which translates to more emby users having playback issues. You really think going backwards in tech is the way forward? I don't even have single device that now has an optical port. Nvidia Shield dumped it long ago. Some of the crap Chinese stuff has it. TVs have an optical output, but again how many have the newer standard. Not very many. And even if they did, the OS would need to recognize it and take a gamble that what's on the other end, also supports it. This spells nothing but problems.

#28 Jdiesel OFFLINE  

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Posted 09 January 2020 - 07:58 PM

Optical out from a TV to a soundbar is still extremely common especially for low end market.

#29 Doofus OFFLINE  

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Posted 09 January 2020 - 08:10 PM

Optical out from a TV to a soundbar is still extremely common especially for low end market.


Yes it is, and how many times have we seen on here people reporting audio problems because they are using optical? It's not like HDMI where it reports it capabilities. It's spin the wheel and see if it works. And if it doesn't, there's loss of audio, either a few channels or the whole thing.

#30 Charlie117 OFFLINE  

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Posted 10 January 2020 - 04:28 AM

 It's an antiquated standard.

 

Well, at least we agree on that.

 

My original request was for an option to select 640 kbps instead of the default 384 kbps. That really shouldn't be an issue for anyone, because again 640 kbps is completely supported by the standard, but for those rare cases that it does cause problems, people can just revert to the default low bitrate 384 kbps. Win-win for everybody.

 

Interestingly enough, these people with the aforementioned issues with 640 kbps should not be able to watch DVDs, Blu-rays, Netflix, Amazon Prime, Disney+ etc. because they all use either a DD+ 5.1 at even higher bitrates that get automatically converted to DD 5.1 640 kbps or they get a DD 5.1 640 kbps natively. By your reasoning, DTS 5.1 core 1509 shouldn't be supported at all. I wonder why I am not reading a ton of issues with all this... probably because it isn't an issue :)


Edited by Charlie117, 10 January 2020 - 04:32 AM.


#31 Doofus OFFLINE  

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Posted 10 January 2020 - 01:44 PM

I will concede :)





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