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xinmiao
07-11-2000, 08:59 AM
Hi,

Can someone please tell me that how the physical intensity of each pixel vary with the R, G, B values? In other words, if 0 represents the minimum intensity and 1.0 represents the maximum, what about the intensity at, say, 0.5?

Many thanks

Gorg
07-11-2000, 10:45 AM
It depends, on your video card and your monitor.

Technically, it should be 1 is twice the intensity of 0.5. But in reality, our eyes catch light in a exponential function. So 1 is less than twice 0.5. This can be adjusted through gamma correction. There are functions in Win32 to adjust the gamma.

Jim Blinn in his book, dirty pixels, explain clearly the gamma correction subject