Ive had this issue since 16.8.1, i've logged it on here, ive also logged a ticked and AMD have still doing nothing about this.
When playing some movies using various DIRECT3D players SDR movies are output with overblown colours, mainly reds. This however only happens in a fairly narrow circumstance but as people are now going 4k this is likely to become a problem for more and more people, mainly HTPC users though to be fair.
I've spent a lot of time looking into whats going on here using different drivers, 3 different graphics cards and two different HDR TV, all reproduce the same problem so it has to be a driver issue, I also think you introduced this with your HDR implementation and I think I know what AMD have done wrong.
This issue in detail is as followes
When you play a 1080p movie in your movie player you can either play it in 1080p and have your TV upscale it have your movie player upscale it before it hits the TV. upscaling has moved on a lot since the first HDR TV came out so it now better for me to have my choice of player upscale, MADVR+MPC or KODI.
When I let me TV upscale it everything is fine, however when I send a 2160p signal to my TV which has been upscaled I get overblown reds as seen here.
However this only happens when i'm outputting in 10 bit, if I dial everything down to 8 bit the problem goes away. I think the issue is that the AMD driver is getting confused somewhere along the DIRECT3D output chain as to what colour space is being played, if you think about it this is understandable as i'm playing an 8 bit movie in 1080p and sending it to my TV as 2160p 10 bit.
So, this is the problem, the driver seems to think that 1080p upscaled material is HDR or something like that, I say this as if I play a native 2160p SDR movie this doesnt happen. All HDR material is output correctly to, so its just 1080p SDR material which has overblown colours.
So to reproduce this you need:
• Play a 1080p 8 bit SDR movie
• Have 10 bit or higher enabled on graphics card and in MADVR
• Set Movie player or MADVR to upscale to 2160p.
• Ensure DIRECT3D 11 10 bit is enabled in MADVR or other movie player
• HDR cable TV/MONITOR/PROJECTOR * unsure about this one.
I have logged a ticket to AMD with this new information but I logged one before and nothing came of it.