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saintfrenz · 01-27-2018, 02:30 PM

Yes, the Intel Graphics Control Panel does allow a choice in color space for output between RGB and YCbCr, and also between Full/Limited range for RGB,
but only if the display is connected to it directly (i.e. though the HDMI on the laptop itself).
When connected through an adapter, I cannot even see the display in the Intel Graphics Control Panel (as expected)
Even when connected directly, the color looks bad when set to RGB (irrespective of Full/Limited) and looks good when set to YCbCr.
However, my laptop has the Intel HD4000 whose pixel clock caps out at 225MHz which means it can only push 4K @ 24Hz.
That's fine for 24p video rendering but awful for desktop use with anything even as simple as a mouse movement being jittery. Hence the whole need for an adapter.

With the Vantec adapter (DL-5500), I tried video playback with hardware acceleration enabled (DXVA with LAV Decoder on Media Player Classic) but was still stuttering a lot. The TV does not have any options for changing RGB range anywhere as far as I could see.

I returned the Vantec adapter (without any more extensive testing) and got a Plugable adapter that has the newer DL-6950 chipset since I was only getting 30Hz with the DL-5500 anyway and the DL-6950 is capable of 4K @ 60Hz.

A note about the TV - every time a new device connects to it and/or connection parameters change (like refresh rate in the monitor settings or the color space in the Intel Graphics Control Panel when connected directly or the HDMI UHD color setting on TV etc)
the TV goes through a "detection" and sets the appropriate mode (one of Cable Box, Blu-ray player, Game Console, PC and Home Theatre System). "PC" mode is the only one in which you get no chroma subsampling i.e. 4:4:4 chroma. Detailed review/settings on this TV is here

https://www.rtings.com/tv/reviews/samsung/mu6300

Results with the new adapter:
1. The video playback issue is now resolved. As a bonus, I also get HDMI bitstreaming with audio. I don't know whether HDMI audio bitstreaming was possible with the Vantec adapter.
2. The color first came just as bad as the first adapter. After setting the HDMI Black Level to "Normal" (as opposed to "Low" before) and flipping HDMI UHD color off and on, it went through the "detection" again and came back with correct color. I had not tried this with the first adapter.

In short, everything is good now. I think there might be some HDMI color space/settings related "negotiation" going on when the TV connects to a device and goes though the "detection" but without further research into the TV and HDMI spec, I can't say.

P.S. from @qp6019352 description, it looked like color crush and not washed out.

01-27-2018, 02:30 PM	#7
saintfrenz Junior Member Join Date: Jan 2018 Posts: 3	Yes, the Intel Graphics Control Panel does allow a choice in color space for output between RGB and YCbCr, and also between Full/Limited range for RGB, but only if the display is connected to it directly (i.e. though the HDMI on the laptop itself). When connected through an adapter, I cannot even see the display in the Intel Graphics Control Panel (as expected) Even when connected directly, the color looks bad when set to RGB (irrespective of Full/Limited) and looks good when set to YCbCr. However, my laptop has the Intel HD4000 whose pixel clock caps out at 225MHz which means it can only push 4K @ 24Hz. That's fine for 24p video rendering but awful for desktop use with anything even as simple as a mouse movement being jittery. Hence the whole need for an adapter. With the Vantec adapter (DL-5500), I tried video playback with hardware acceleration enabled (DXVA with LAV Decoder on Media Player Classic) but was still stuttering a lot. The TV does not have any options for changing RGB range anywhere as far as I could see. I returned the Vantec adapter (without any more extensive testing) and got a Plugable adapter that has the newer DL-6950 chipset since I was only getting 30Hz with the DL-5500 anyway and the DL-6950 is capable of 4K @ 60Hz. A note about the TV - every time a new device connects to it and/or connection parameters change (like refresh rate in the monitor settings or the color space in the Intel Graphics Control Panel when connected directly or the HDMI UHD color setting on TV etc) the TV goes through a "detection" and sets the appropriate mode (one of Cable Box, Blu-ray player, Game Console, PC and Home Theatre System). "PC" mode is the only one in which you get no chroma subsampling i.e. 4:4:4 chroma. Detailed review/settings on this TV is here https://www.rtings.com/tv/reviews/samsung/mu6300 Results with the new adapter: 1. The video playback issue is now resolved. As a bonus, I also get HDMI bitstreaming with audio. I don't know whether HDMI audio bitstreaming was possible with the Vantec adapter. 2. The color first came just as bad as the first adapter. After setting the HDMI Black Level to "Normal" (as opposed to "Low" before) and flipping HDMI UHD color off and on, it went through the "detection" again and came back with correct color. I had not tried this with the first adapter. In short, everything is good now. I think there might be some HDMI color space/settings related "negotiation" going on when the TV connects to a device and goes though the "detection" but without further research into the TV and HDMI spec, I can't say. P.S. from @qp6019352 description, it looked like color crush and not washed out.