Re: [Openexr-devel] Introduction and CTL/ICC question

[Greg Ward]

Hi Kai-Uwe,

If you are interested in utilizing the code in Photosphere for 
tone-mapping in Cinepaint, you can download the HEAD release of 
Radiance from www.radiance-online.org:

        http://www.radiance-online.org/software/snapshots/radiance-HEAD.zip

While parts of this OpenSource C code are still being ported to 
Windows, the routines you are interested in are fully portable between 
architectures as far as I know.  In the ray/src/common subdirectory, 
you will find the files:

copyright.h
tmap16bit.c
tmapcolrs.c
tmapluv.c
tmaptiff.c
tmaptiff.h
tmerrmsg.h
tmprivat.h
tonemap.c
tonemap.h

The main routines are explained in tonemap.h and implemented in 
tonemap.c.  Specialization functions in tmaptiff.c, tmap16bit.c, and 
tmapcolrs.c implement fast conversions for TIFF LogLuv, 16-bit integer, 
and Radiance RGBE pixel types, respectively.  The library is built for 
speed of loading and tone-mapping high resolution images, and is quite 
fast.

Copyright restrictions are spelled out in the file "copyright.h", but 
are quite reasonable.

-Greg

> From: Kai-Uwe Behrmann <address@hidden>
> Date: March 11, 2005 5:59:06 AM PST
>
> Sorry, I had a misunderstanding of the term tone reproduction as the 
> term
> colour reproduction.
>
> Am 11.03.05, 07:09 -0500 schrieb Geraldine Joffre:
>
> > I am under the impression that what you are after is the ability to 
> > handle tone and color
> > reproduction of HDR images via ICC profiles. Is this correct? In this 
> > case, you may want to
>
> I saw such behaviour within Greg Wards photosphere application. Well 
> it is
> very different from the ICC concept of "one colour at one time" 
> handling.
> Tonemapping introduces frequencies, handling the neighbourhood of 
> colours
> as well.
>
> First I would like to adapt a tonemapping implementation to CinePaint.
> Then I may go more seriously in such a discussion.
>
> regards
> Kai-Uwe Behrmann
>                                 + development for color management
>                                 + imaging / panoramas
>                                 + email: address@hidden
>                                 + http://www.behrmann.name