Re: Interaction of pCAL and gAMA
John Bowler <[email protected]>
| Newsgroups | gmane.comp.graphics.png.general |
|---|---|
| Message-ID | <CAP7U398JT8Peex-q0MeKwAnXD1WSg=B0S_uUcv5W1L2JPdeJGw@mail.gmail.com> |
On Thu, Jan 21, 2016 at 4:56 PM, Glenn Randers-Pehrson <[email protected]> wrote: > Here's an interpretation that maybe makes more sense: Ignore gAMA and use > pCAL > to recover the physical data. Ignore pCAL and use gAMA to view the image, > but > don't expect the image to be pretty. If there's pCAL but no gAMA, assume > sRGB > when displaying the image. One could use pCAL to construct a legend to > display > along with the image. > Ah well, in my context prettiness is an absolute requirement. Actually I think it is in any practical use of pCAL; the point is to store a PNG which contains a visualization of the data isn't it? I can't see a lot of point (actually, any point) otherwise; Portable Network Data? Ho ho. It can be made moot, though it is a bit baroque; in my case if the linear value is used the units are cd/m², if not they are (cd/m²)^gAMA. Of course I still need to know what the authoritative answer is; it has to be one or the other. A related question is whether anyone knows a convention for representing exponents unambiguously using only Latin-1 characters. ^ is pure geek obviously. It's weird, I can do x³²¹º but Latin-1 stops at three ;-), so cd/m², fine, but no decimal point for the gamma exponent value and no 4-9. John Bowler ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=267308311&iu=/4140 _______________________________________________ png-mng-misc mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/png-mng-misc