Float32 colorspace range

Bart Coppens kde at bartcoppens.be
Sun Sep 11 15:12:28 CEST 2005

For the float32 histogram I needed to know what the minimum and maximum values 
were for a single channel. I remembered reading something about those colors 
being in the 0.0 - 1.0 range, and that made it very easy to implement Views 
in the code. When I checked it with an openEXR image, the histogram looked 
fine to me.
However, as I was playing around a bit today with openEXR images in 
histograms, I checked some actual values from an image. I got values back in 
the range -0.00001 (probably rounding error or so, so I'd still guess it 
starts at 0.0), to over 200.0, which is far over 1.0 The only reference I 
seem to find in the code is:
#define FLOAT_MAX 1.0f //temp
Which isn't really true it seems. Does anyone know the real range so that that 
can be fixed in the histogram code?


More information about the kimageshop mailing list