Lost all frequencies above 30Hz

After the last OSMC update (that was offered to me yesterday/today), I lost all refresh frequencies above 30 Hz.

They are not offered in Kodi and the projector also reports only 2160p30 being used.

Is that a known problem? What do I look out for?

cat /sys/class/amhdmitx/amhdmitx0/disp_cap                            480p60hz
576p50hz
720p60hz
1080i60hz
1080p60hz
720p50hz
1080i50hz
1080p30hz
1080p50hz
1080p24hz
2160p30hz
2160p25hz
2160p24hz
smpte24hz
smpte25hz
smpte30hz
smpte50hz420
smpte60hz420
2160p50hz420
2160p60hz420

Hi,

For best results, you should set the GUI to 1080p and enable Adjust Refresh Rate instead of setting the GUI to 4K.

We do not recommend setting the resolution to 4K under Kodi settings.

This would be caused by this patch:

Sam

Yes but the non-420 modes are not coming through. Can you post cat /sys/class/amhdmitx/amhdmitx0/edid and cat /sys/class/amhdmitx/amhdmitx0/rawedid please @LubosD

I’m happy with the GUI being at 2160p, but I’ll keep it in mind.

Does it mean that from now on, 50/60 Hz will only be used (in this 4:2:0 case of mine) if the content has such a high refresh rate?

No, I think there’s bug

root@osmc:~# cat /sys/class/amhdmitx/amhdmitx0/edid
Rx Brand Name: DON
Rx Product Name: DENON-AVR
Manufacture Week: 0
Manufacture Year: 2017
Physical size(cm): 0 x 0
EDID Version: 1.3
EDID block number: 0x1
blk0 chksum: 0xf5
Source Physical Address[a.b.c.d]: 2.5.0.0
YCC support 0x03, VIC (native 255):
ColorDeepSupport 0xb8 10/12/16/Y444 1/1/0/1
6 21 2 17 4 19 5 20 16 31 32 34 1 93 94 95 98 99 100 3 7 18 11 15 26 30 22 14 35 36 29 95 94 93 98 352 353 357 358
Audio {format, channel, freq, cce}
{1, 7, 0x7f, 0x07}
{7, 5, 0x1e, 0x00}
{2, 5, 0x07, 0x00}
{11, 7, 0x7e, 0x03}
{10, 7, 0x06, 0x03}
{12, 7, 0x7e, 0x03}
{11, 7, 0x7e, 0x01}
Speaker Allocation: 0x5f
Vendor: 0xc03
MaxTMDSClock1 300 MHz
ColorMetry: 0xd7
SCDC: 0
RR_Cap: 0
LTE_340M_Scramble: 0
  HDR  DeepColor
checkvalue: 0xf5640000
root@osmc:~# cat /sys/class/amhdmitx/amhdmitx0/rawedid
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

Thanks. We’ll get that fixed.

Running the GUI at 2160p will cause worse performance and a worse picture — just so you are aware.

Your TV will have a better scaler than Kodi

Sam

In particular, Kodi’s handling of artwork (poster, fanart, thumbnail, etc.) is a real problem when setting the GUI to 4K.

When caching artwork, Kodi grabs whatever artwork source you have, then reduces the resolution to match the <imageres> and <fanartres> settings (default for OSMC a height of 540 pixels for posters, and 720 pixels for fanart) if necessary. Then, this reduced resolution image is then used whenever the GUI needs to display the image.

This means a poster that takes up 75% of the vertical space would be scaled up from 540 pixels to 810 on a 1080p GUI, which looks OK, but not great. On a 4K GUI, though, it will be 1620 pixels high, and that will look pretty bad, since the algorithm used is very basic. The <imagescalingalgorithm> setting is only used when creating the initial small image (downscaling), not when scaling up on the GUI. This is supposed to change with Leia, but I don’t know it if has. Even so, a 3x upscale is still a lot, even for lanczos or a bicubic spline.

A solution to this is to increase the <imageres> and <fanartres> settings, but making them large enough that a 4K GUI looks good will result in a massive cache database (about 1GB per 75 videos with a full set of images).

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I’m looking into this, but do you realise you will never get 10 bits at 4k60Hz? You may well find sending 10-bit 4k60Hz video at 1080p60Hz gives you a better picture (less banding).

AFAIK, most 4k video is HDR and therefore 10-bit.

No, I had no idea. I don’t understand the full relationship between chroma subsampling and HDR. Does 4:2:0 preclude 10-bits or is it something else you see in the EDID?

That being said, my projector did recognize/indicate when HDR content was being played at 2160p60.

HDR is always 10-bit (or more). But you can send only 8 of those 10 bits and no device in the HDMI chain will complain. You just get banding on HDR displays because HDR stretches the highlights in the picture.

Any bitdepth can be used with any chroma subsampling except 422 with 16 bits IIRC.

Your beamer can handle a TMDS clock rate of up to 300MHz on which you can send 4k60Hz at 4:2:0, 8-bit but 10-bit needs a clock-rate 25% higher.

Just for future reference: in order to get 600 MHz bandwidth witb Denon’s receivers, one has to go to Video settings and switch the 4K mode to “Enhanced”.

If this is not selected, the receiver will clamp to 300 MHz regardless of what the projector or the cabling can do.

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