2015-12-31, 07:10
@afedchin
I think you're sort of right. The projector is connected via a 15m in wall cable and two short cables at either end of that (receiver to wall < 15m in wall cable > wall to projector). This works perfectly (and has done for over a year) with YCbCr (4:4:4) mode. I've tried alternate cables at either end but can't change the wall cable obviously. The 15m wall cable is a certified high quality HDMI 2 cable and I tested it extensively when the walls were off and never saw any issue with it, so I'm pretty confident in it - but it IS a long distance.
I suspect RGB mode uses higher bandwidth somehow, and/or for whatever reason the signal being output in RGB mode is weaker. (I've ordered a powered HDMI repeater box to see if that can help).
In any case, in YCbCr mode everything seems to work fine. I understand in theory that RGB mode is better to use due to less conversions, but I have today thrown a bunch of calibration tests at both the plasma and projector including grey ramps, colour and resolution tests etc, and I can't detect any visual difference). I won't say both modes are perfect - there is some minor lack of smoothness in the grey ramp - but the results are visually identical in YCbCr and RGB at least.
(For good measure I compared an OE 6.0 installation on the same hardware as well, and it shows the same display as DX11 Kodi. So I don't think I am losing anything by YCbCr mode and it sure beats weird flickering and purple/green stripe issues. I like OE for quick boot & simplicity but the sluggish remote speeds and lack of support for e.g. Steam streaming, and general state of Linux/AMD support is ... not awesome).
I believe (well, various forum postings cliam...) that AMD APUs are known for not outputting a massive amount of video signal (perhaps as a keep cool thing?)...but it seems I have a workable solution for Jarvis until I next upgrade hardware.
(One thing of note and theoretical advantage is the AMD drivers show 10 bit output with YCbCr and only 8 bit with RGB).
I think you're sort of right. The projector is connected via a 15m in wall cable and two short cables at either end of that (receiver to wall < 15m in wall cable > wall to projector). This works perfectly (and has done for over a year) with YCbCr (4:4:4) mode. I've tried alternate cables at either end but can't change the wall cable obviously. The 15m wall cable is a certified high quality HDMI 2 cable and I tested it extensively when the walls were off and never saw any issue with it, so I'm pretty confident in it - but it IS a long distance.
I suspect RGB mode uses higher bandwidth somehow, and/or for whatever reason the signal being output in RGB mode is weaker. (I've ordered a powered HDMI repeater box to see if that can help).
In any case, in YCbCr mode everything seems to work fine. I understand in theory that RGB mode is better to use due to less conversions, but I have today thrown a bunch of calibration tests at both the plasma and projector including grey ramps, colour and resolution tests etc, and I can't detect any visual difference). I won't say both modes are perfect - there is some minor lack of smoothness in the grey ramp - but the results are visually identical in YCbCr and RGB at least.
(For good measure I compared an OE 6.0 installation on the same hardware as well, and it shows the same display as DX11 Kodi. So I don't think I am losing anything by YCbCr mode and it sure beats weird flickering and purple/green stripe issues. I like OE for quick boot & simplicity but the sluggish remote speeds and lack of support for e.g. Steam streaming, and general state of Linux/AMD support is ... not awesome).
I believe (well, various forum postings cliam...) that AMD APUs are known for not outputting a massive amount of video signal (perhaps as a keep cool thing?)...but it seems I have a workable solution for Jarvis until I next upgrade hardware.
(One thing of note and theoretical advantage is the AMD drivers show 10 bit output with YCbCr and only 8 bit with RGB).
