Washed colors in 4K transcoded to HD / SD

[sooty234 266]

You didn't read correctly. I said HDR shows not movies. I have multi versioning for movies. But for shows, there are massively more. Multi versioning for shows would be insane. It's double digits each season, not just one video, like a movie.

Edited November 26, 2020 by sooty234

[Carlo 4560]

Same for me, movie or show, doesn't matter.

[sooty234 266]

Well, if you have the space then that's ok. I don't have enough room for that much storage. And I would think most people don't have that kind of storage, either. So tone mapping is essential.

[Carlo 4560]

Totally agree with you we need it and that it would help a lot of people out with storage requirements.

What we don't know however is how many transcodes can be done at one time or how robust CPU/GPU will need to be to do this right. Going from 4K HDR to 1080 SDR is very taxing on the system especially when you need to do it faster than real-time.

[vdatanet 1617]

Just now, cayars said:

Totally agree with you we need it and that it would help a lot of people out with storage requirements.

What we don't know however is how many transcodes can be done at one time or how robust CPU/GPU will need to be to do this right. Going from 4K HDR to 1080 SDR is very taxing on the system especially when you need to do it faster than real-time.

I've done that test, using an i5 8600 (not a high end processor). It can handle at least 4 transcoding sessions 4K to 1080p tone-mapping using hardware acceleration using linux. Later I will try if it can handle more sessions, I don't have more Plex clients to test. That looks promising! 

[Carlo 4560]

With GPU I think we're fine but CPU is very questionable.

[vdatanet 1617]

Just now, cayars said:

With GPU I think we're fine but CPU is very questionable.

That's true, I've also tested disabling hardware acceleration, just one transcoding sessions takes about 100% CPU and the CPU is KO

[sooty234 266]

I've not tested this, but my 1st gen TR will probably do at least 6. I might test that at some point. 

19 minutes ago, vdatanet said:

That's true, I've also tested disabling hardware acceleration, just one transcoding sessions takes about 100% CPU and the CPU is KO

Processor at 100% doesn't necessarily mean it can't do more. Four transcodes on my TR will push it to 100%, but It can do 10 with ease.

[vdatanet 1617]

7 minutes ago, sooty234 said:

I've not tested this, but my 1st gen TR will probably do at least 6. I might test that at some point. 

Processor at 100% doesn't necessarily mean it can't do more. Four transcodes on my TR will push it to 100%, but It can do 10 with ease.

Oh that's true, I also can do 4 transcoding sessions with hardware acceleration disabled. After first session CPU is at 100%, so I didn't try more sessions, but if I play more sessions, they transcode fine.

 

[sooty234 266]

Yup! Transcoding 4k isn't that hard. It's a misnomer. It's encoding the output is the big part. Decoding isn't taxing. So it's the HDR tone mapping that's important.

[Carlo 4560]

49 minutes ago, vdatanet said:

 I don't have more Plex clients to test. That looks promising! 

Just open a few tabs in your browser and playback.

23 minutes ago, sooty234 said:

I've not tested this, but my 1st gen TR will probably do at least 6. I might test that at some point. 

TR=Thread Ripper???

[sooty234 266]

1 minute ago, cayars said:

TR=Thread Ripper???

Yeah.

[sooty234 266]

I just tried playing in chrome with multiple tabs. That used to work, but now the server craps out. Looking at the dashboard, it looks like the server is getting confused between what is playing.

[vdatanet 1617]

18 minutes ago, cayars said:

Just open a few tabs in your browser and playback.

3 sessions is good, the 4th makes the system unstable and the 5th, well there's no 5th session, it doesn't even begin.

[vdatanet 1617]

Just now, sooty234 said:

I just tried playing in chrome with multiple tabs. That used to work, but now the server craps out. Looking at the dashboard, it looks like the server is getting confused between what is playing.

Ahhh, I was a bit confused, using 4 different devices it worked fine, but tabs in the same browser makes the system unstable.

[sooty234 266]

2 minutes ago, vdatanet said:

Ahhh, I was a bit confused, using 4 different devices it worked fine, but tabs in the same browser makes the system unstable.

Yeah, I think this a server bug. So that should be a different topic.

[vdatanet 1617]

Anyway I think it is proven that a quantum computer is not necessary to transcode with tone-mapping, obviously we cannot do it with a Pi, we need a decent CPU.

[sooty234 266]

But keep in mind that tone mapping requires more processing. So how this holds up is something we'll have to re-test.

[Carlo 4560]

Out of curiosity can one of you try burning in subs while tone mapping a 4K to 1080 and see how that works?

[vdatanet 1617]

24 minutes ago, cayars said:

Out of curiosity can one of you try burning in subs while tone mapping a 4K to 1080 and see how that works?

I can't do that. I've tested Apple TV with native player (PGS subtitles not supported). It can't handle that, because is encoding to H264 4K and then bitrate is huge (more than double), I don't think the player can handle that. But the same occurs with server tone-mapping disabled.

Edited November 26, 2020 by vdatanet

[sooty234 266]

I don't have plex, so I can't test tone mapping. But in emby

13:51:24.051 Stream mapping:
13:51:24.051   Stream #0:0 (hevc) -> scale
13:51:24.051   Stream #0:20 (pgssub) -> scale
13:51:24.051   overlay -> Stream #0:0 (libx264)
13:51:24.051   Stream #0:4 -> #0:1 (copy)

 

Edited November 26, 2020 by sooty234

[vdatanet 1617]

1 hour ago, sooty234 said:

But keep in mind that tone mapping requires more processing. So how this holds up is something we'll have to re-test.

My tests are done using the latest Plex beta with support for tone-mapping during transcoding. Keep in mind that I do not want to advertise Plex, I am a 100% Emby user, I just want to provide data to be taken into account.

Edited November 26, 2020 by vdatanet

[Carlo 4560]

I haven't gotten the chance to play with it yet in Plex.  I'm kind of interested in the results I'll get if installed on my i7 Emby Server without QuickSync but with Windows Server and Nvidia GPU.  So this should only be CPU.  I also have a i5 notebook with QuickSync running Windows 10 which should allow limited GPU use.  Maybe I'll get to it by the weekend.

[rbjtech 5284]

14 hours ago, vdatanet said:

Anyway I think it is proven that a quantum computer is not necessary to transcode with tone-mapping, obviously we cannot do it with a Pi, we need a decent CPU.

.. and this is the crux of the matter.  I'm still running a 1st Gen i5 as my main Emby server, as I try to eliminate transcoding wherever possible by having multiple resolution copies.  In a non transcoding scenario, even a Pi could stream multiple 4K Remux's - but as soon as you need ANY form of transcoding - it all goes to pot - and my i5 cannot even transcode one 4K SDR stream, yet alone tonemap.

Storage is cheap vs a server upgrade, so this is the route I have taken - but the option to tonemap should definitely be implemented for those that want to take that path and have the hardware available.

Interestingly, Netflix don't live transcode/tonemap, they use multiple resolution copies on their own CDN network ... so I'm still not convinced even if we could easily tonemap, that this is the best solution to the problem.  It's an interesting topic ... 

 

[vdatanet 1617]

22 minutes ago, rbjtech said:

.. and this is the crux of the matter.  I'm still running a 1st Gen i5 as my main Emby server, as I try to eliminate transcoding wherever possible by having multiple resolution copies.  In a non transcoding scenario, even a Pi could stream multiple 4K Remux's - but as soon as you need ANY form of transcoding - it all goes to pot - and my i5 cannot even transcode one 4K SDR stream, yet alone tonemap.

Storage is cheap vs a server upgrade, so this is the route I have taken - but the option to tonemap should definitely be implemented for those that want to take that path and have the hardware available.

Interestingly, Netflix don't live transcode/tonemap, they use multiple resolution copies on their own CDN network ... so I'm still not convinced even if we could easily tonemap, that this is the best solution to the problem.  It's an interesting topic ... 

Yes, storage is cheap but time is very expensive. I just need casual transcoding, 95% of my HDR sessions are direct play, for the remaing 5%, I prefer to have a powerful enough system to transcode 4K HDR rather than duplicate my content, not because of the storage used but because of the work it takes, you have to rip your material twice. If necessary, I prefer to upgrade my server.

Edited November 27, 2020 by vdatanet