[Libexif-devel] Re: ICC profile API?

[Ross B. <ro...@bu...>]

Hubert wrote:
> Ross Burton wrote:
> > I"m trying to build the pieces required so that a normal X desktop can
> > display colour-calibrated images [1].  So far I"ve got a tool which sets
> > a property on the root window containing the ICC profile for the screen,
> > and a growing patch to Eye Of Gnome which extracts any ICC profile or
> > calibration data and uses Little CMS to correct the image before
> > display.
>
> Really interesting. Any plan integrating that in GNOME ? :-)

Funny you should ask that, Hub. ;)

I'd really like to see gdk-pixbuf expose the ICC profile for any image
file directly, so that applications can access it easily and calibrate
it.  I'd also like to see the ICC profile setter integrated into
gnome-settings-daemon, but this would probably require the forever put
off rewrite of the Resolution capplet.

> > As EoG is using libexif to read the EXIF file, and reading ICC profiles
> > is very similar to reading EXIF chunks, I was wondering if the libexif
> > developers would consider adding support for ICC profiles to the API?
> > An ICC profile is stored in JPEG files as a set of APP2 chunks, which
> > start with "ICC_PROFILE\0" followed by a sequence number.
> > 
> > If you think this is a good idea I"ll happily try and come up with an
> > API design and then a patch, but I wanted to have your feedback before
> > starting.
> 
> Shoudln"t be a problem. Where is that documented ? I missed something.

The specification for embedding ICC in JPEGs (etc) is in section B5 of
http://www.color.org/ICC1V42.pdf.  Basically its in an APP2 section,
with the string "ICC_PROFILE\0" and a sequence byte attached.

Ross
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Ross Burton                                 mail: ro...@bu...
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