Transcoding videos with Dolby Atmos and 4K

[eph77341 3]

Hello everyone,

I have a small problem with the transcoding of videos. I have often had problems with videos not running smoothly or not running at all when Emby was running directly on an Acer H340. So I thought I'd try a mini PC hosting the Emby server and connected to the NAS (all via cable).

Now when I start a 4K movie with Dolby Atmos directly on the TV, I see that the video is transcoded, but it doesn't run smoothly. If I start the same video on an XBox Series X, it is also transcoded, but the audio track.

Is it possible to set Emby so that the audio track is not transcoded? Or how can I tell that Emby wants to transcode the Dolby Atmos track? The Xbox (and according to the data sheet and settings also the TV) should actually be able to do this.

Translated with DeepL.com (free version)

[rbjtech 4816]

Unless your playback equipment can natively playback the video and/or audio, then it will attempt to transcode so that you get a picture and sound.   It may not necesarily be the best combination, because if you have to transcode, then it generally effects BOTH video and audio streams.

So taking an example - if your playback device does not support Dolby TrueHD but does support Dolby Vision - then it will forced to transcode the stream, thus you LOSE the Dolby Vision - resulting in just an SDR video and perhaps Dolby Digital sound.

The solution is -

a) Use media/convert media that is compatible with your hardware OR

b) Use playback hardware that plays all the media types - Nvidia Shield is still probably the most compatible if you need HD Audio, but something like the latest FireTV sticks are also very good for common 'streaming' formats. 

[eph77341 3]

So i found out that it may be a problem with the Emby App.

https://emby.media/community/index.php?/topic/130604-official-android-tv-app-not-passing-truehd-audio-through-the-tv/#comment-1372001

So i tried using Kodi on Xbox with Emby plugin and my receiver is showing Atmos and emby server says direct play for everything.

But now the video is stucking every ~20 seconds. Could it be too much data to stream? 

[RanmaCanada 422]

It could be. Video game consoles are a horrible playback device sadly, and they do cause nothing but problems. To go back to your first post, the "server" you were using is a horribly underpowered machine from 2010 with an Intel Atom processor. It will not be able to transcode anything, period. The Atom Z30 that is in there has a passmark score of 183, that is basically a glorified calculator. What are the specs of the system you are currently using? 4k needs modern hardware with hardware decoding/encoding support to function properly if your playback devices can not direct play content. Is your current system hardwired, or wireless?

[rbjtech 4816]

If it's direct play, then there is a high chance it is bandwidth related.  If it's 4K with True-HD then I'm assuming it's likely a remux - so you are looking at 60-80 Mbit/sec required to 'stream'.   Unless you have decent Wifi then you will struggle.  You may also find the wired ethernet interface is only 100Mbit - so again, it may struggle.

[eph77341 3]

My "calculator" is working ok with FHD, but in 50% of cases the cinema Intro Trailers are not working so i bought from Amazon Asin: B0BVV27M3N with alder Lake n95. 

I assumed that it could be because of wlan so i changed to LAN, still the same Problem... 

If i Turn off subtitles it gets a bit better, but still stuckin2g... 

[rbjtech 4816]

Logs will tell us what is going on.  By the sounds of it, we need to see the ffmpeg logs as it's transcoding.

[eph77341 3]

Xbox_Kodi_Stucking.txtTV_Emby_Stucking.txtXBox_Emby_NotPlaying.txt

So i have tried this:

On Xbox i used Emby and Kodi-App. With Emby the video is not starting, with Kodi it's playing but stucking after few seconds.

On TV it's transcoding Atmos to Surround and it's stucking...

[rbjtech 4816]

You are playing a DV7 Remux (the Samsung device does not support DV but will fallback to HDR10) BUT it's the Audio that is forcing the transcode.    Your transcoding is not fast enough to keep up with realtime.  (0.7x only).  You need faster transcoding via a much faster CPU, Intel Quicksync GPU or via Nvidia GPU. (Premier required for GPU transcoding)

OR

Playback media that is compatible with your hardware - if you were to choose the AC3 audio track instead (with no subtitles as they are PGS) - it SHOULD direct play with no transcoding.

Edited July 20, 2024 by rbjtech

[eph77341 3]

So for working with my TV i need an emby server with nvidia gpu? Any recommendations? 

But should the xbox be able to manage it? 

[rbjtech 4816]

xbox cannot playback True-HD Audio - have you tried just playing the AC3 track as I suggested ?

[eph77341 3]

But the i Do Not get the atmos Sound? 

[rbjtech 4816]

2 minutes ago, eph77341 said:

But the i Do Not get the atmos Sound? 

No - None of your equipment supports Dolby True-HD with Atmos audio.

[eph77341 3]

And why is xbox with kodi showing Sound as atmos and direct play? 

Would it be better to invest in nvidia shield and streaming via calculator Server than in an emby server? 

[eph77341 3]

Now i tried a raspberry pi 5 with Libreelec installed and connected a HDD with Video.
It's playing Atmos fluently.

But same raspberry with embycon is stucking.

It's connected via LAN. Does it mean that my NAS is too slow?

[Neminem 698]

Yes !! You server cant keep up, see marked in red.

The number should be over 1.

12:42:51.120 elapsed=00:00:00.94 frame=   93 fps=0.0 q=-1.0 size=N/A time=00:00:00.07 bitrate=N/A throttle=off speed=0.0754x    
12:42:51.996 elapsed=00:00:01.82 frame=  117 fps= 64 q=-1.0 size=N/A time=00:00:01.06 bitrate=N/A throttle=off speed=0.584x    
12:42:52.496 elapsed=00:00:02.32 frame=  129 fps= 56 q=-1.0 size=N/A time=00:00:01.57 bitrate=N/A throttle=off speed=0.679x    
12:42:53.341 elapsed=00:00:03.16 frame=  148 fps= 47 q=-1.0 size=N/A time=00:00:02.31 bitrate=N/A throttle=off speed=0.73x    

 

[eph77341 3]

I think you both refer to the same number. But I thought this is for transcoding?

2 hours ago, jaycedk said:

The number should be over 1.

12:42:51.120 elapsed=00:00:00.94 frame=   93 fps=0.0 q=-1.0 size=N/A time=00:00:00.07 bitrate=N/A throttle=off speed=0.0754x    

On 7/20/2024 at 1:31 PM, rbjtech said:

Your transcoding is not fast enough to keep up with realtime.  (0.7x only).  You need faster transcoding via a much faster CPU, Intel Quicksync GPU or via Nvidia GPU.

So do I have to upgrade my NAS or the PC which is hosting Emby?

 

[Neminem 698]

Yes you neglected to supply log from that.

Lets see logs from using embycon.

But better server hw would help you a lot.

Ether that or stop trying to stream videos that dos not direct play.

Edited July 21, 2024 by jaycedk

[hjason7812 28]

On 7/20/2024 at 8:11 AM, eph77341 said:

So for working with my TV i need an emby server with nvidia gpu? Any recommendations? 

But should the xbox be able to manage it? 

no you don't need a gpu in your server box.
I have no gpu and it runs fine, i have an old motherboard from gigabyte well here is a pic of my cpu i am using. and it plays dolby atmos and dolby vision movies and tv shows just fine. although sometimes it give me a hard time because of the size of the video. anything above 40 gb's for some reason truenas doesn't like to play it loves to give a little hard time. even though everything is 100% direct play, i still haven't figured out why or how to fix that. but yeah my motherboard has hdmi out via the onboard gpu chip and my cpu works as a gpu as well due to it being for gaming..

[Carlo 4484]

Apples & Oranges

His Atom Z30 has a CPU passmark score of 183, t.
Your AMD FX-9370 has a CPU passmark score of 6207

If he's only able to transcode at 0.7x speed, it's not fast enough.