Originally Posted by mpgxsvcd
So many people don't understand that the HDR content is stored ungraded and that natively it should look washed out. Because there is no definitive color standard at the moment for HDR the color grading must be done in real-time by the TV or player.
There is a definitive standard for the gamma transfer, it's been adopted by SMPTE as ST-2084. There is also a definitive color standard, it's bt-2020. Within that bt-2020 color space which encompasses all of rec 709 and P3, you can scale the RGB primaries and white point for any subset with st-2086 metadata. The grading per se has already been done by a colorist and is baked into the HEVC file. What the display or player must do, is a matrix transformation to RGB in accordance with the gamma table used by the display
Right now your TV is automatically adjusting the washed out picture so that it gives the “HDR” affect. The content is stored ungraded on the disc. If it was stored graded then what specification would they grade it to? If they graded it to something less than what your TV is capable of then you would lose color fidelity when your TV graded it again to utilize its full capabilities. If they grade it past the capabilities of your TV then you would get clipped colors.
The reason the picture appears washed out is because the display doesn't have st-2084 transformation, only 709. With uncompressed video, it's possible to transform between one mapping and the other, but once the video has been compressed to 709 (HEVC is lossy), the upper highlight stops are compressed into just a few shades and become under represented by the bit budget.
It's going to be the case that an HDR player can output HDR or SDR to a display from an st-2084 video transfer. An HDR capable display can do the same thing but why would it? It already plays both types!
So what's left? A 4k display without HDR and without a player has no means to transfer st-2084 to rec 709 gamma, so the image will play flat.