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joie
06-02-2010, 10:09 AM
Hi there;

What is the diference between EXR RGBA 32bit format and EXR RGBE 8bit format?, both opened in photoshop are read as 32 bit float images, the only difference is RGBE has no alpha info...

Thank's for the answers :)

ctrl.studio
06-02-2010, 03:57 PM
RGBE is the ward radiance format. in E you have a shared exponent ... to turn the 8bits RGB channels into 32bits ...

if (rgbe[3]) {
f = ldexp(1.0,rgbe[3]-(int)(128+8));

*red = rgbe[0] * f;
*green = rgbe[1] * f;
*blue = rgbe[2] * f;
}

max

joie
06-02-2010, 05:37 PM
OK, it's an exponent..., so, is it the same to render 8bit RGBE as to render 32bit RGBA EXR format?.

naik
06-04-2010, 10:56 PM
umm think of it as 8bit on steroids

haha , i like that!

Ash-Man
06-04-2010, 10:56 PM
No, RGBE will not give you the same range like 32 or 16 .
but you can get away with it in some situations
umm think of it as 8bit on steroids :)

joie
07-12-2010, 12:16 PM
As RGBE doesn't have any alpha information..., Wich pass should I use to get one?, I've tried "matte" and "opacity" passes but both of them come black.

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07-12-2010, 12:16 PM
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