What is the pupil dilation effect in computer graphics called?

[font=sans-serif][size=2]Gamma Correction?[/font]
[font=sans-serif][size=2]
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[font=sans-serif][size=2]http://en.wikipedia.org/wiki/Gamma_correction[/font]

-ddn

Either that or Tone Mapping.

[font="sans-serif"]Gamma Correction?[/font]
[font="sans-serif"] [/font]
[font="sans-serif"]http://en.wikipedia....amma_correction[/font]

-ddn

Either that or Tone Mapping.

[color=#1C2837][size=2]I don't think either of those are actually directly referring to what I speak of. They are more like general categories that are related to what I'm talking about. Is there no real name for this operation?

High dynamic range rendering?

Half life lost coast had a nice example of this that I always remember: http://en.wikipedia.org/wiki/Half-Life_2:_Lost_Coast Under the bit about HDR it says

The final version of Valve's HDR technology adds a significant number of lighting effects to the engine, aimed at making the game appear more realistic. Bloom shading was introduced, blurring bright edges in the game world and emulating a camera's overexposure to light.[7] This is combined with exposure control to tailor the effect to represent the human eye. For example, as the player exits a dark area into a light area, the new area is initially glaringly bright, but quickly darkens, representing the adjustment of the player character's eyes to the light[/quote]

There's this one referance that mentions it too, page 2 of http://www.bit-tech.net/gaming/pc/2005/06/14/hl2_hdr_overview/1

Exposure control possibly. http://en.wikipedia.org/wiki/Exposure_(photography)

High dynamic range rendering?

That's another general term that covers many different rendering effects such as hdr bloom among others.

[quote name='Tachikoma' timestamp='1314432232' post='4854349']
High dynamic range rendering?

That's another general term that covers many different rendering effects such as hdr bloom among others.
[/quote]

Not that I know, many effects are added on-top of HDR to simulate more effects (like bloom). But HDR (high dynamic range) is simply the process of rendering all the colors as-is without clipping, so that you can afterwards simulate the sensitivty of the eye, by clipping the rendered colors to what is determined to be actually visible by the eye. That is, very loosely speaking, you render colors from 0 to INF as the appear and then you might determine the average visible light intensity to be 100, so you only render the colors within the range 80-120. As the light intensity goes up or down, so does the average and also the range you clip to (just like the pupil adjusting to varying light intensity).

It's hardly a very good scentific explanation but I think you understand the idea... and as far as I can tell, it is exactly what you are looking for.

[quote name='SteveDeFacto' timestamp='1314433071' post='4854352']
[quote name='Tachikoma' timestamp='1314432232' post='4854349']
High dynamic range rendering?

That's another general term that covers many different rendering effects such as hdr bloom among others.
[/quote]

Not that I know, many effects are added on-top of HDR to simulate more effects (like bloom). But HDR (high dynamic range) is simply the process of rendering all the colors as-is without clipping, so that you can afterwards simulate the sensitivty of the eye, by clipping the rendered colors to what is determined to be actually visible by the eye. That is, very loosely speaking, you render colors from 0 to INF as the appear and then you might determine the average visible light intensity to be 100, so you only render the colors within the range 80-120. As the light intensity goes down, so does the average and also the range you clip to.

It's hardly a very good scentific explanation but I think you understand the idea... and as far as I can tell, it is exactly what you are looking for.
[/quote]

I understand the concept but I still don't know what it's called... You're talking about changing the luminance but that's really not the right way to do it. You are suppose to change the brightness of the scene right before the bloom effect which would do what you are talking about but it would work more like pupil dilation.

Yes, I understand the idea but I still don't know what it's called...

High Dynamic Range (Rendering)... http://en.wikipedia....range_rendering

???

EDIT: Or ah, you are talking about the "algorithm" to compute the light intensity of the scene... or?

EDIT: Or ah, you are talking about the "algorithm" to compute the light intensity of the scene... or?

That and changing the brightness. High Dynamic Range Rendering combines all effects into one term but I'm looking for the specific term.

[quote name='Syranide' timestamp='1314440500' post='4854373']
EDIT: Or ah, you are talking about the "algorithm" to compute the light intensity of the scene... or?

That and changing the brightness. High Dynamic Range Rendering combines all effects into one term but I'm looking for the specific term.
[/quote]

The little I've looked into it, HDR usually is just about the rendering without clipping and mapping, but at the same time used as a name for all of it. Perhaps HDRI (imaging) is a bit more narrow, I'm not really sure... I'm personally not aware of any single term for just the "core" other than possibly subjective use of HDRR or HDRI ... but those may seem to encompass additional optional effects too by others.

Here's one article that goes into a bit of everything it seems, including the core ... http://www.cg.tuwien...ltimeHDR%20.pdf , perhaps there's something in there of interest.

To the point, it would be good to know WHY you need a specific term so that we could better help you.

EDIT: Perhaps as mentioned above, "Tone mapping" might be what you are looking for, although it's only the process of extracting visible light I believe. But really, the rendering of unclipped colors is hardly an algorithm of any kind I'd guess, so I doubt you'll find a name for that other than "high dynamic range (imaging?)".

Are you looking for (log-?)average luminance? http://www.gamedev.n...minance-adjust/

Basically you want to simulate auto-exposure. There are a lot of ways to do it...the most common way is to determine an auto-exposure "key value" based on the average (or log-average) of luminance, and every frame slowly interpolate from the current exposure to the new exposure using some sort of adaptation rate.

Do you mean eye-adaptation? It's that or auto-exposure, like MJP said, but the later is more of a camera term than an eye one. In real-time graphics they're the same thing. Not sure about everywhere else though.