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DX11 Dark Area Darker and Bright Area Brighter

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Hello Guys,

 

When I edit the texture in photo editing software to make the bright areas brighter and the dark areas darker, I get much better results with HDR, so I thought about doing it in pixel shader instead.

 

How do I write a pixel shader that makes the dark areas darker and bright areas brighter?

 

I'm using DX11 / C++ and rendering the scene in HDR.

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output = max(input * scalar + offset, 0)
Having a scalar > 1 will make brighter pixels brighter, having an offset less than 0 will make dark pixels darker, you may lose color information with the dark pixels.

This approach will duplicate the brightness/contrast function of most image programs. Did you use any other color adjustment functions when adjusting manually?

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@HappyCoder: It seems that I'm losing details and the scene appears to be burned out.

 

How do I get greater color range in the image without losing the details so I can take advantage of HDR?

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