image - How is HDR data stored? -

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i wondering data structure behind storing images hdr data. understand how regular images (rgba) , cubemaps stored. doubt simple storing multiple images @ different exposures inside same file.

you've moved on long ago, thought worth posting references else happened upon question.

here old reference radiance .pic (now .hdr) file format. useful info starts @ bottom of page 29. http://radsite.lbl.gov/radiance/refer/filefmts.pdf

excerpt:

the basic idea store 1-byte mantissa each of 3 primaries, , common 1-byte exponent. accuracy of these values on order of 1% (+/-1 in 200) on dynamic range 10^-38 10^38.

and here more recent reference jpeg hdr format: http://www.anyhere.com/gward/papers/cic05.pdf


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