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HDR format?

Posted: 2012-08-13T05:11:40-07:00
by Alan Hadley
What is the internal (ram) format of an HDR channel? I was reading about IM and HDR, in one place it says 'C double' which I understood to be 64 bits for this size, and further down the page it says '32 bits' which I thought was 'C float'.

I am asking because I am including some fast single channel processing in my program, this uses 'float' format so that SSE2 can do 4 maths operations in a single step, (I am using SSE2 assembly language on all available cores). So obviously a 32 bit HDR option would suit my application.

Alan Hadley

Re: HDR format?

Posted: 2012-08-13T05:21:13-07:00
by magick
Pixels in HDRI are float, not double. Operations on the HDRI pixels uses doubles but the results are stored internally as 32-bit floats.