Colorspaces of the driver for stills and video

Hi there back after a wile.
i was a bit busy, still are, and stumbled on a question lately. wile playing with photo developing and softproofing and thus colormanagment.
ICC profiles, embedded colorspace tags of files and such.
Rather confusing stuff i must say. :sweat_smile:
Say i produce a jpeg in sRGB IEC61966-2.1 and the same in Display P3 (which will be the future screen colorspace)
and i use the viewer in OSMC to view my images on screen.
1 does recognise vero4k embedded colorspace tags?
2 which colorspace profile’s does it actually handle?
3 can we manage this behaviour in settings? (flow chart is : Colormanagment by ICC in vero4k and sent out towards a commercial smart tv Oled which has it’s own Colormanagment of caorse.)
if vero4k is limitted to sRGB/AdobeRGB as ICC, P3 would be crushed before sending.

any insight in this matter?

Forgive my ignorance, but why wouldn’t this be better handled by having separate sRGB and P3 calibration presets on the display?

i think i am the ignornant here :wink:

i tested my files in a few viewers.
Faststone Viewer which has the same out come as vero4k viewer and my TV


(left P3-file right sRGB file)
and FRV (Fast RAWViewer)
colormanagment off

colormanagment on

Back to your question:

tried to find some info about the screens capable colorspace support.
found none.
reading this;

Leading OLED displays that can reproduce up to 96 – 98% of DCI-P3 can replicate a maximum of 75% of Rec.2020.

So i think that seeing above vero4k hasn’t CM in profiling can’t find anything about it in settings.

It’s not something I’ve looked into, but I understand Kodi uses ffmpeg to render still images. As such, there should be the capability to use an embedded profile to convert the image data to the colourspace of the display. However

  • I don’t know if the ffmpeg that ships with Kodi is set up to automatically do that, and
  • Kodi (at least the version OSMC ships) is not set up to output still images in anything other than 8-bit BT709 colours, so you won’t get the wide colour gamut you might be looking for.

All things are possible but the Pictures part of Kodi doesn’t get a lot of love (see also requests to output still images at 4k resolution).

Because you would need to know the colourspace of every image and adjust the presets for each of them?

Right that would be a tiny issue :grinning:

i would like a way to use the full capability’s of the screen.
probably a barebone on w11 and plex (have a life account) and a proper colormanagment set up would do the trick but i would like to use my vero4k a bit longer because it’s connected towards my yamaha reciever on hmdi and this gives me 5.1 DTS DD and such.
somewhere along the way i probably end up swapping all my audio systems for easy stuff like ARGHHHH sound bar systems… :grimacing: :roll_eyes: and virtual surround system…
But for now i am trying to just update/ upscale/ improve my standing system.

colormanagement is the new alice in wonderland rabbithole. :joy:

No. That is exactly the issue. If you have images that use the full DCI-P3 gamut what you want is those to be sent to your display without crushing them into BT709/sRGB gamut on the way through.

You want your TV to tell Kodi ‘I can display wide colour gamut - send me your pictures encoded in BT2020 or DCI-P3 colourspace and I’ll display nearly all the pixels correctly’. That happens automatically for video but I don’t think it happens for still images.

Now if you are really after colour fidelity the other thing to consider is calibration of the display. Vero4k does not support ICC display profiles so you have only got the controls on the TV to adjust the colours it actually puts out. Luckily, modern TVs have lots of knobs to twiddle but to do it properly you need a colorimeter and lots of patience.

Fact: The hardware and software can handle P3 right but only for video apperantly.
Right?

But that colorspace profile is probably seated in the containerdata of the movie.

It would be great if the stills can be shown in bigger colorspaces.

The video pipeline (when HW accelerated) and photo pipeline are very different.

Video is hardware decoded by the SoC and put on to a rendering plane directly; photos will be decoded by ffmpeg and presented via GLES.

In theory, the SoC could handle this and the presentation layer directly, but Kodi doesn’t have a method of accelerating this via a HW decoder and everything goes to ffmpeg.

Sam

Bt709 and sRGB is about the same colorspace.
So screengamut is evolving above this colorspace.
If ffmpeg is the software could it be plausible that they evolve too in time?

To be clear the resolution for photo’s is always native?
4k on vero4kplus and 4k on smart tv means still are shown in 3840x2160 resolution?
Or is that too limited to 1080x1920 same as the menu?

Ffmpeg already has all the capabilities to convert between colourspaces. So if you view an image tagged as DCI-P3 or with an embedded ICC profile I think ffmpeg will do the colourspace conversion to the colourspace of the Kodi desktop (sRGB on a PC monitor). Have you compared your two images in Kodi on PC?

No. The framebuffer for the GUI is only 1920x1080 so all images are reduced to that if bigger than HD. There are performance issues with increasing the framebuffer size.

And @sam_nazarko
The colorspace limited for srgb isn’t a big issue (it is often enough) but the resolutionlimitation issue of Full hd (1080p) is a bigger “disapointment”.
Now my screen is 55 inch 4k so resolution wise it’s doable in 1080p but not ideal.
If the screen would be enlarged towards 65 inch or 70 inch i think it starts to show on regulair viewing distance.
Don’t get me wrong the vero4k isn’t bad.

Thinking of the general use case of the product.
1 netflix, and such are providing enough posibilities for most people for series and movies.
2 plex provides also a home stored library on nass or such and is for serie and movies a solid alternative.
Plex supports also full ress photo’s according to there support site.

The vero4k supports hardware decoding and 5.1 reciever support. It’s a small device so very portable.
Most people like the kodi platform.
It’s a great way to smart up (upgrade procesing power) your older TV.
It plays almost every video you throw at it.

But it loses ground on versatility of multimedia.
The hardware around it is charging right and left ahead.( screens/tv’s audio units barebone pc’s.

I still love it as concept, it’s stable and cheap and still it does alot without much effort.
Windows pc’s uses much more juice( power) even in barebone concept.
Most smart tv’s are not powerfull enough to have the same sound experience or user interface flexibility.

I don’t know how much trouble it is to upgrade some parts.
1 a viewer which can handle photo’s and mpegvideo at 4k (native resolution of the hardware.)
Home video and photo’s are often grouped together in a folder.
2 colorspace setup. Srgb,adobe and P3. (Those are most used or gonabe the most used profiles for viewing screens.)

Personal consideration, reflection,

I am moving from one house to an other and this could be a push, endorsment to reconsider the livingroom multimedia setup in the near future.
My first idea is bare bone and plex with 4k and hdmi 2. Something for audio support.
This would let my nass plexserver be obsolete(processingpower has less headroom for the future) and get me a dedicated NUC who’s not only streams towards the TV in the livingroom but also streams to any other media device in my family.
This way i have one library to maintain and one system to learn and maintain.

Regards Peter.

Now you are confusing me. You started off enquiring about colourspaces, but now

Each of us has to decide the best hardware and software for their particular circumstances - budget and media library. There is no ‘one size fits all’. As I said, Kodi doesn’t major on still image reproduction. I think you’ll find most ‘media centres’ are similarly focussed on video and audio playing. And FOSS software developers will often get around to supporting the latest hardware only when users clamour for it.

But thanks for your feedback.

Could be.
Let me elaborate.
All yesterdays til today, sRGB was big enough for viewing on televisionscreens.
Not many tv’s where able to show much bigger. The new technology is going more mainstream and does stretch color gamuts and thus the possibilty of using bigger colorspaces on jpegs like adobeRGB or display P3 are today something to consider.
So i liked to see my images in P3 Which oled can handle for 98%.
An other mainstream of tv’s is 4k nowaday’s. And because also bigger tv’s are more mainstream viewingdistance is often the same so resolution has a bigger effect on viewing your image. Video or photo.
The fact that stills arn’t in 4k send to a tv is therefore a bigger issue for people who watches there photo’s on there television in the livingroom.

Yes true, and often shifts the needs for those hardware and software.
The fact that movies and series are more and more on demand by streamings compagnies like Netflix who have also DD audio send with there series and movies.
The low res stereo streaming is long behind us. Smart TV’s don’t need anymore for most streamings apps external processingpower.
Most people i know have a new smart tv of 65inch or bigger and uses alkinds of apps on that for streaming with a soundbar as audio. The developing slope for processingpower inside smart tv’s is leveling the last years.

That’s more what i try to say. The amount of buyers for linux Kodi devices who are buying them just for the cinema experience when connected to a 5.1 system are getting thinner.

True.
I am using plexamp for a wile on my mobile on the road and it serves me well.
I can wile driving rate my musiclibrary in stars and update this also at the same time on my nass. Set up this system on my family’s phones if they like. My synology nass runs the plex server which i can use as streaming library on all kind of devices of my family.
At this moment i use it mostly for mp3 streaming. Because i am afraid my nass isn’t powerfull enough to stream multiple video at HD or 4k.
Another thing what is a present demand at homes.
My kids never uses the veroplus any more, they just start up youtube or netflix or prime and don’t bother about the lack of surroundsound.

It’s just an observation.

In a way which compensates only for the different transfer function, or which actually takes account of the different colour gamut as well?

I may be jumping to conclusions but since ICC profiles are supported the nuts and bolts are there for any arbitrary colourspace transform. There’s not much detail in their docs.

At the risk of derailing the thread entirely(!) there’s at least one video-playback case where this is of relevance: the colour gamut to which many NTSC DVDs are mastered is noticeably different from the rec.709 gamut. Televisions often (for all I know, maybe universally) fail to take this into account, which means that you get over-saturated colours when playing NTSC DVDs and their remuxes. Use of an appropriate ICC profile could compensate for that, I think. But I’m not aware that Kodi does this at the moment - I think it only deals with the differences in the YUV->RGB formulae.

Anyway, just rambling, sorry! :grinning:

Almost all 70, 80 and 90 movies which are converted from 4:3 to 16:9 has that color issue.
Or you see strange effects due maunal refreshed colors or due the fact that old movies are rendered , converted to 16:9 by cut off or the worse one stretching have often icc transfers.

Often not a real issue because it looks as old so you accept it.
But now if you watch a digital made (greenscreen) movie with larger colorspaces and the player can’t cope with AdobeRGB or Display P3 it’s hopefully with rendering intent perceptual. To smooth it out. Plain clipping does strange things.
From the moment consumer screens have larger gamuts this shows even more.
My sony has an great rendering chip X1-processor and even a special made netflix icc. So it can get nice colors and sharp upscaling even on older resolutions and flatter looking colors. Looks great, i tested the same panel in LG c2 and that smart tv is much more “game color looking”

Point is you never know which color is as intended by the movie/serie maker.
On photo’s this is even more a “thing” because you look longer at the same frame.

Before my sony i used a old 1080p FHD led tv so sRGB was normal and bigger was not supported. Same as resolution on stills. Didn’t needed anything else.
Now the end hardware can handle more resolution and bigger colorspaces so then the vero become in some cases a venturi/limitation in the possibility’s.

My set up is not high end stuff so i think lots of users stumble into this area.