More observations after looking directly at your files: 1. My current trunk build matches *your* build. So again, I think that one is correct.
2. Both the Ubuntu and your own build say they are 1.6.11, so I don't have a good explanation about what's going on. Are you really sure the Ubuntu one is not built with OCIO? If it was, that might explain it, since it would be a color conversion not known to OCIO so it may just turn it into a no-op (whereas nowadays, even if OCIO support is present, if OCIO doesn't know "sRGB" space, OIIO will step in and take over at that point). 3. Another curiosity -- your original file does not contain any color space tags, neither a gamma value (1.0 would mean linear) nor an "sRGB intent" flag. I would expect (hope?) that most png files ought to contain one or the other, just to give some clue about what color space it thinks it's in. So it's really hard to discern what the "correct" appearance ought to be. > On Jan 4, 2018, at 11:40 PM, Larry Gritz <[email protected]> wrote: > > By the way, based on the examples you posted, it seems to me that the one you > built yourself is "correct", in the sense that if you do a color > transformation from sRGB to linear, I expect it to have lower values (look > darker, if viewed with the same response curve). The one that you said was > made by the Ubuntu package doesn't seem to have changed at all, which > certainly seems wrong to me. > > >> On Jan 4, 2018, at 11:36 PM, Larry Gritz <[email protected] >> <mailto:[email protected]>> wrote: >> >> Well, we went a few rounds of trying to decide how the different cases >> >> 1. Built without OCIO >> 2. Built with OCIO, but no OCIO config found at runtime >> 3. Built with OCIO, OCIO config found, but doesn't have a "sRGB" space in >> the config >> 4. All stars align, OCIO and it knows sRGB >> >> should match or not, and what they should do. There have been several >> patches about this over the years. >> >> I think that some time in the 1.7 days, we improved this by finally deciding >> that 1-3 should all agree and do the "right" thing. >> >> The mismatch you're seeing with two builds of 1.6 probably either means that >> they were built from two different commits that straddle some change in this >> logic (or something else related), or else perhaps you aren't correct about >> them both being build without OCIO. >> >> FYI, the currently supported stable release is the 1.8 series. If you're >> already considering building your own, I would recommend not fooling around >> with the Ubuntu OIIO 1.6 package, skip directly to 1.8 if you possibly can, >> and see if it fixes the cases you're interested in. If it does, it's >> probably not worth trying to figure out the fine points of why 1.6 is not >> having the behavior you want. (If 1.8 or later is still not doing what you >> expect, then I definitely want to figure out why.) >> >> -- lg >> >> >>> On Jan 4, 2018, at 11:53 AM, Jordi Torres <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> Hi again, >>> >>> I disabled it in cmake on purpose, because the packaged one is not compiled >>> against OpenColorIO. >>> >>> Anyway as far as I understand OCIO should not interfere in srgb to linear >>> conversions, am I wrong? >>> >>> Thanks. >>> >>> 2018-01-04 17:50 GMT+01:00 Larry Gritz <[email protected] >>> <mailto:[email protected]>>: >>> Were either built with OpenColorIO support enabled? >>> >>> >>> >>> >>> On January 4, 2018 8:43:43 AM PST, Jordi Torres <[email protected] >>> <mailto:[email protected]>> wrote: >>> Hi Larry, >>> >>> Mainly 1.6.x versions. >>> >>> Thanks. >>> >>> 2018-01-04 17:40 GMT+01:00 Larry Gritz <[email protected] >>> <mailto:[email protected]>>: >>> Which versions of oiio are they? >>> >>> >>> >>> >>> On January 4, 2018 8:13:40 AM PST, Jordi Torres <[email protected] >>> <mailto:[email protected]>> wrote: >>> Hi all, >>> >>> I'm pretty new to this library, so forgive my ignorance if I say somethign >>> dumb. >>> I'm having different results with the command: >>> oiiotool test.png --colorconvert sRGB linear -o out.png depending if I use >>> my own compiled oiiotool or I use the Ubuntu packaged one. >>> >>> It happens with different oiio versions. I'm running Ubuntu 16.04. >>> >>> Attached the results. Does it ring a bell for anybody? >>> >>> Thanks. >>> -- >>> Jordi Torres >>> >>> >>> >>> -- >>> Larry Gritz >>> [email protected] <mailto:[email protected]> >>> >>> >>> >>> -- >>> Jordi Torres >>> >>> >>> >>> -- >>> Larry Gritz >>> [email protected] <mailto:[email protected]> >>> >>> >>> >>> -- >>> Jordi Torres >> >> -- >> Larry Gritz >> [email protected] <mailto:[email protected]> >> >> >> >> >> _______________________________________________ >> Oiio-dev mailing list >> [email protected] <mailto:[email protected]> >> http://lists.openimageio.org/listinfo.cgi/oiio-dev-openimageio.org > > -- > Larry Gritz > [email protected] <mailto:[email protected]> > > > > > _______________________________________________ > Oiio-dev mailing list > [email protected] > http://lists.openimageio.org/listinfo.cgi/oiio-dev-openimageio.org -- Larry Gritz [email protected]
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