Could Valve add HDR to Half-Life and Portal for example? I’m still unsure why it has to be implemented on a “per game” level, why can’t just the screen do some white-level raising and black-level lowering on all scenes?

I must be misunderstanding how HDR works

  • MeatSafeMurderer@alien.topB
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    1 year ago

    It needs to be implemented per-game because of quantization. See, tonemapping operators are reversible, meaning you can feed in a tonemapped image into the inverse tonemapper and get an exact duplicate of the non-tonemapped HDR image. Well…you can provided it hasn’t been 8bit quantization. If it has then there are only 255 possible values, because it throws away everything in between as part of the process, meaning that even once you do the inverse tonemap there still only 255 possible values, only now there is a vast gulf of possible brightness between 254 and 255. As an example, maybe 254 is 300 nits, and 255 is 3000nits. Well that’s going to be noticeable, even more noticeable than the banding when just using SDR.

    In order to implement HDR properly it needs to be implemented before quantization.

    • philhzss@alien.topOPB
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      1 year ago

      Okay, thank you. It’s more involved than I thought, it’s not just “more contrast”

      • gusthenewkid@alien.topB
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        1 year ago

        There is a great application called Specialk that can add HDR in most DX11 games, not sure if it’s available on Linux though.

        • philhzss@alien.topOPB
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          1 year ago

          Hmmm, could be interesting. But maybe not worth it if it has to be implemented at such a deep level for it to work well