HDR format?

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Alan Hadley
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HDR format?

Post 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
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magick
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Re: HDR format?

Post 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.
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