Vero 4K H265 movies (8-bit encoded only?) - blacks show as grey, colours washed out (reduced colourspace)

Help and Support Vero 4K / Vero 4K +
61

Hi,

I’d happily settle for the Vero 4K to output these full-range h265 8-bit using the same clipping approach as the Pi - it’s far more watchable than the washed out grey alternative.

Thanks

62

Hi,

Thanks for your feedback.

Is this with Vero 4K?

When the video mode changes, can you type dmesg | paste-log and send me the URL?

We can definitely do that as a minimum.
Starting with that is probably best.

If you are not heavily invested in your setup or happy to take a backup, could you try a 2017.12-1 image from Download - OSMC? See Reinstalling OSMC - Vero 4K - OSMC for more details on how to do this.

I think my banding and rounding fixes were too aggressive and are applying to all content types which is a regression. We only need this for 4K HDR material. This is probably the quickest to test.

It’s always great when dealing with a sysadmin and dev who isn’t shy of the command line :slight_smile:

Sam

63

Hi Sam,

You’re up late!

I’ve just powered down all the systems, but will plan to tackle your suggested approaches later today.

The tests were all conducted on the Vero 4K.

I’ll get you the dmesg output, and then look to installing the 2017.12-1 image. I think that’s the one I’ve already got prepared on a 64GB microsd (we talked about a full reinstall somewhere near to start of the thread).

I’ve customised the Vero, but have bavpckups of my settings and scripts, so the only issue is recreating the Media Source entries - is there a human readable file holding the entries, paths, source (local usb hdd, samba, etc) content type etc? If so I’ll take a backup.

More than happy to get stuck in debugging this, especially if it aids the project as a whole.

Thanks

64

Hi @retroresolution

Indeed!

Should be under /home/osmc/.kodi/userdata/sources.xml
For good measure, you can tar up ~/.kodi. After reinstalling stop Kodi with sudo systemctl stop mediacenter and untar. You can then start again with sudo systemctl start mediacenter.

Much obliged

Sam

65

Hi,

Apologies, yesterday was rough, and I’ve had another night without sleep.

I hope to perform some testing today and revert to you with my findings,

Regards,
RR

66

No problem, take your time.

67

Hi Sam,

The only test I’ve performed so far is as follows (rebuilding the Vero with the recommended image was too much to do today, sorry) -

  • I connected the Vero 4K via HDMI to the 1080p ‘e-motion’ TV.

  • In 'Settings | Player | Videos ’ I set 'Adjust display refresh rate’ to ALWAYS.

  • In 'Settings | Player | Videos ’ I ensured ‘Sync playback to display’ was not enabled (e.g. left at default setting).

  • I rebooted the Vero

I then played a few seconds of the following, before issuing dmseg |paste-log

  • 3 different full range 8-bit h265 files which exhibit the colourspace problem

  • 1 8-bit h265 which plays correctly (unsure if this is full range or not, I need to find my notes…)

  • 1 10-bit h265 which plays correctly.

The TV could be seen to switch display modes at the start and end of each playback test, although the OSD always reports 1080p @ 60hz.

The log file url is:

https://paste.osmc.tv/siguhuzoxu

Many thanks

68

Thanks for confirming.

I will check those logs shortly in more detail.
Your Pi does not appear to adjust refresh rate. Can you confirm if you see the same problem with this option enabled?

I am surprised you do not see the issues on Pi with a CEA mode.

Sam

69

Hi Sam,

I wonder if I’ve misunderstood something here; you said that my Pi isn’t adjusting refresh rate, however the logs are from the Vero.

Could you tell me exactly which tests to perform, with which settings, on which device, so I can get you the right information?

I hope I’m not confusing the issue here.

Cheers,
RR

70

Hi

When you ran vcgencmd during playback, it seems to show your output to still be at 60Hz. That is how I concluded that a change in refresh rate was not occurring on your Pi.

So I did wonder if this is why you didn’t see the issue there.

I’m about to release an update, then will look in to this again more closely.

Cheers,

Sam

71

Hi Sam,

Unfortunately due to health issues I’ve not yet had the wherewithal to backup then reinstall the Vero 4K with the 2017.12-1 image.

As per our previous discussion, I wrote:

I’d happily settle for the Vero 4K to output these full-range h265 8-bit using the same clipping approach as the Pi - it’s far more watchable than the washed out grey alternative.

To which you replied:

We can definitely do that as a minimum.
Starting with that is probably best.

I’m wondering if there’s a command I can run via SSH when a problematic 8-bit HEVC file is playing to force the reduced colourspace (in a similar manner to the earlier approaches to forcing HDR modes).

I maybe grasping at straws with this, as with most coding issues what sounds simple usually entails a deep rabbit-hole to navigate, but I thought it worth asking.

Best wishes
RR

72

At the moment, I’m actually not sure why things look different for you just yet.

In theory:

echo 1 | sudo tee /sys/devices/virtual/amhdmitx/amhdmitx0/output_rgb

should do it.

Sam

73

Hi Sam,

Thanks for the suggestion; before I try this, does this act as a toggle (permanently setting the reduced colourspace on), or is it to be run for each video played? If the former, I assume sending ‘echo 0’ instead of ‘echo 1’ would reverse the operation?

Many thanks,

74

Hi,

The sysfs node was added in a cheap and cheerful manner and setting it to 0 will not swap it back. You can reboot to do so however.

It is persistent for the session after being set (updates an internal flag which is evaluated on every mode switch)

Sam

75

Hi,

Understood, thanks,

I’ll give it a try and report back

76

Cheers, let me know how you get on.

77

Hi,

Unfortunately issuing the command made no difference to any of the H265 8-bit full colourspace files I’ve tested :frowning:

Regards,
RR

78

Okay, thanks for letting me know. I will test again tomorrow and see if I can scratch my head for any ideas.

Sam

79

Hi Sam,

Thanks for looking into this again.

I’m very much hoping you can resolve the issue; sadly my Vero 4K is largelly gathering dust, as, for whatever reason, the vast majority of my movies are in this apparently non-standard full-colourspace 8 bit format (i didn’t rip them myself).

Were you able to reproduce the issue using the edited snippets I uploaded?

Regards,

RR

80

Hi RR

Sorry for the staggered replies. I’m about to go on holiday and will be catching a flight in a couple of hours, so it’s a late rush around here.

I tried your snippets and couldn’t immediately see an issue here. If others would like to try, please give this a go: https://collab.osmc.tv/s/A5q4UPN128FJZxI.

I will have Internet on my travels, as well as access to a display so I will take the opportunity to test on that display as well. I’m hunting down a different YUV420 issue as well – but perhaps the issue is related after all.

I will also (perhaps not while travelling) test with a HDFury Vertex on Pi and Vero 4K to see if there is a difference in the output signal. If there is, it will likely provide an answer as to why the playback looks different for you on the two platforms.

Sam