Transcoding HDR

[Kyrunner 86]

I have emby running on a Qnap TVS672N 32 GB of memory. 
 

when I watch a 4K HDR movie on my IPad if I’m not home I like to lower the quality Down and Emby will start to transcode. I have hardware transcode only set but the video is really dark is there a setting I need change. 

[WhackOBill 8]

I've got a similar issue which brought me to your thread.

Transcoding a single 4K HDR stream to 1080p non-HDR brings my Emby server CPU to its knees ... all cores at 100%.  And the transcoded output is still not correct with some odd green lines at an angle and the color and brightness all wrong.

I've only got two 4K HDR capable displays, the rest are 1080 non-HDR.  I'm wondering what the right path is to help with this issue?  Do I need to up my server to an EPYC or Threadripper or Xeon for this to work?  Is there a hardware solution ... for example, adding GPUs and enabling hardware transcoding?  I've got a GTX 1050 lying around but I'm not sure if the FFMPEG that comes with Emby will properly employ the resources.

Any thoughts?

[Happy2Play 9783]

Transcoding HEVC HDR is extremely resource heavy in a none hardware environment.  But there are dozens of topics on this.

We would need to see the server and ffmpeg logs for an example and probably the hardwaredetection log also.

 

 

[Luke 42083]

Hi, yes let's please look at an example. Thanks.

[WhackOBill 8]

Thanks.  The Tone Mapping thread was very informative.  It seems I might be due for a media server upgrade to Gen 12 Intel which should provide what I need for the foreseeable future.  Or make use of that 1050 card as a resource in my older machine.

It looks like I need to move to the 4.7 beta release to get these features in the built-in FFMPEG library.  Currently on 4.6.7.0.

[RanmaCanada 497]

the latest version of the beta should be able to do cuda tonemapping with your 1050, as per my conversation with softworks who corrected me on my assumptions.  But yes, 4k transcoding needs serious power.  A full software transcode of 4k needs at least 17k passmark, hardware based can be done on far less.  I use a laptop with an 8130u (passmark of 3682) as my server and have no issues when using quicksync (hardware).  

4K HDR (50Mbps, 10-bit HEVC) file: 17000 PassMark score (being transcoded to 10Mbps 1080p)
4K SDR (40Mbps, 8-bit HEVC) file: 12000 PassMark score (being transcoded to 10Mbps 1080p)
1080p (10Mbps, H.264) file: 2000 PassMark score
720p (4Mbps, H.264) file: 1500 PassMark score

Edited December 1, 2021 by RanmaCanada

[Carlo 4561]

Adding a mediocre/mid-price Nvidia GPU should be a lot cheaper then an upgrade to a CPU with dozens of threads.
You'll likely get more transcodes as well and not run nearly as hot.