Hi Marco,
Thanks a lot! Would you be able to take a quick look at my changes ?
Commit is here:
https://github.com/GrokImageCompression/grok/commit/8d62e2252fefd4a15124cac73c7f47a65fde651d
and complete file is here:
https://github.com/GrokImageCompression/grok/blob/master/src/bin/jp2/convertpng.cpp
Existing code already had some code for gamma curve, so perhaps I need to
disable that?
Cheers,
Aaron
On Tue, Feb 21, 2017 at 2:28 AM, Marco Freudenberger <
marco.freudenber...@entrustdatacard.com> wrote:
> Aaron,
>
>
>
> I might be able to help a little.
>
>
>
> You need to write the iCCP chunk. Also make sure you have no conflicting
> entries in other chunks (sRGB, gAMA, cHRM chunk). PNG is a bit delicate in
> terms of possible ambiguous color space info in header.
>
> You also need to know, that some PNG readers don’t handle the color space
> chucks gracefully (specifically gAMA, cHRM – even Photoshop is clunky in
> that aspect, at least if no iCCP chunk is present).
>
>
>
> Do you use libpng ? If so, you need to do call
>
> png_set_iCCP()
>
> during your file creation to write the ICC profile.
>
>
>
> Marco
>
>
>
> *Von:* Noel Carboni [mailto:ncarb...@prodigitalsoftware.com]
> *Gesendet:* Montag, 20. Februar 2017 13:03
> *An:* 'Aaron Boxer'
> *Cc:* lcms-user@lists.sourceforge.net
> *Betreff:* Re: [Lcms-user] Apply profile with PCS = cmsSigXYZData, Color
> Space = cmsSigGrayData
>
>
>
> >Noel, do you know where I could find sample code to read/write ICC
> profiles for PNG format?
>
> Sorry, I really don't, offhand. I'd probably rely heavy on Google for
> that.
>
>
>
> -Noel
>
>
>
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, SlashDot.org! http://sdm.link/slashdot
_______________________________________________
Lcms-user mailing list
Lcms-user@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/lcms-user
