I have KS8000 and have it on for all ports, especially so for the q10 pro as am quite sure if set off, it will not auto negotiate to turn it on when watching HDR/HEVC 10-bit content (BT.2020)  ... so just turn them ON, haven't seen any deterioration even with 1080p content/devices. 

Is the Kodi supplied with custom firmwares are that of HiMedia version of it or the stock Android version from Google Play?

Also, what is the package named HiPQTools under /system/app/? Is it the Imprex Engine file, can I remove it safely from .zip? If so, does it mean there will be no added effects from this Engine, which I prefer. As I prefer to remove all the Gmail, Browser and other such apps not required from the folder to make the system cleaner, before flashing.

Hi everybody. I am a new user and decided to repost my reply from Kodi forum here:

Tips and Tricks:

    Q5/Q10 Pro Output Info Diagnostic Tool by @pcristi
    See @OlivierQC's helpful video tutorials here.
    Don't care for Imprex engine? Here's how to minimize its effects and get better blacks & whites...

        (2016-04-21 20:54)BigPines Wrote: 
        One thing I should point out is that the external player is always processing the image even after disabling Imprex. I found that both whites and blacks are crushed even with Imprex off and image settings set to standard. So unfortunately, there is no true pass-through available on the device as it is always altering the image. I reported this problem to Himedia during the pre-production testing and I have confirmed the problem exists on the production hardware as well. The work-around I found was to turn off all Imprex options and set Brightness to 66 and Contrast to 43. This eliminates crushing on both blacks and whites. I used a test pattern from Digital Video Essentials to confirm this.

Unless it is already mentioned but not on the first page - you can actually turn Imprex OFF. Briefly my setup is 4K HDR10 (Sammy KS8000 EU model) + AV Receiver (Denon X1300W). First you go to Settings->Advanced and select "SDR" under "TV HDR Mode", then launch a movie and Turn Off Impex, then head back to "Advance Options" and select either "Auto" or "HDR10" if your TV supports it. I have compared the scenes with my older HTPC and indeed there is no processing happening, about 99% is turned off. Imprex is definitely no go, too much effects and post-processing.

The only issue I am having, a major one, is actually with the HDR content. I have tried quite a few options and it seems that the current Q10 Pro's "Video Color Space & HDMI deep color" is not working properly. I have, as of today, latest custom 1.07 firmware and set at 2160/60p with YcbCr420 10Bit" (UHD content produced in 4:2:0). When I compare Life Of Pie (HDR 10bit HEVC 24fps) launched on TV via USB (or external HDD) to how Q10 Pro reproduces via HiMediaPlayer, you can see clearly that the dark scenes are not dar enough, colours are not vivid and there is major greyishness present as if it is 8bit source. I have tried many-many settings and combos and it is no go. I hope the newer firmware will solve this issue soonest.

The other two major issue, perhaps related with Kodi Android version (as I was using it on a HTPC Linux built) are:
- No settings for DTS-HD and Dolby TrueHD in Kodi - thus, they do not reproduce correctly. Only correctly when played via Himedia Wrapper from inside Kodi, including the Dolby Atmos.
- It seems that as of now HEVC 10-bit & HDR is not fully supported by Kodi 16.1 - right?
- And, unlike HiMediaPlayer, the Kodi built-in player has issues with FPS matching - think all play at 60fps.