color gamut conversion

Archived from groups: rec.photo.digital (More info?)

Peter Vermeer wrote:
> Hi,
>
> I'm interesting in the sequence of events of light which comes from an
> arbitrary scene, travels through a digital camera, and ends in a
> picture (e.g. bmp-file).
>
> Does anybody know some good references / Websites about this topic?


These links were just posted in another thread:
<http://cs.haifa.ac.il/hagit/courses/ist/Lectures/IST12_...;
<http://wwwde.kodak.com/US/en/corp/researchDevelopment/t...;


>
> For example I read something about color gamut conversion that happens
> when the sensor color space is converted to another color space (e.g.
> RGB).
> Can anybody explain something more about this? For example what is the
> sensor color space? Why is it necessary because you already apply the
> Bayer matrix which gives you RGB values, I thought?


All devices have their own distinctive bias so standardized test charts
and color reading machines create software profiles to quantify the
imperfections. Also various devices and formats have limited range so
you need to specify how to translate or clip from one gamut to another.

Archived from groups: rec.photo.digital (More info?)

Peter Vermeer wrote:

> Hi,
>
> I'm interesting in the sequence of events of light which comes from an
> arbitrary scene, travels through a digital camera, and ends in a
> picture (e.g. bmp-file).
>
> Does anybody know some good references / Websites about this topic?
>
> For example I read something about color gamut conversion that happens
> when the sensor color space is converted to another color space (e.g.
> RGB).
> Can anybody explain something more about this? For example what is the
> sensor color space? Why is it necessary because you already apply the
> Bayer matrix which gives you RGB values, I thought?
>
>

The main reason for "working" color spaces is they are based on a central
grey point. That means you can adjust contrast etc without shifting the
color balance. Trying to use say a printer profile as a working color space
is a BAD idea..
--

Stacey

Archived from groups: rec.photo.digital (More info?)

Peter Vermeer <logiclips@yahoo.com> wrote:

> I'm interesting in the sequence of events of light which comes from an
> arbitrary scene, travels through a digital camera, and ends in a
> picture (e.g. bmp-file).

> Does anybody know some good references / Websites about this topic?

The classic reference on this topic is:

The Reproduction of Colour, 6th Edition
R.W.G. Hunt
ISBN: 0-470-02425-9
Hardcover
724 pages
September 2004

http://eu.wiley.com/WileyCDA/WileyTitle/productCd-04700...

Andrew.

Archived from groups: rec.photo.digital (More info?)

Peter Vermeer wrote:
>
> Hi,
>
> I'm interesting in the sequence of events of light which comes from an
> arbitrary scene, travels through a digital camera, and ends in a
> picture (e.g. bmp-file).
>
> Does anybody know some good references / Websites about this topic?
>
> For example I read something about color gamut conversion that happens
> when the sensor color space is converted to another color space (e.g.
> RGB).
> Can anybody explain something more about this? For example what is the
> sensor color space? Why is it necessary because you already apply the
> Bayer matrix which gives you RGB values, I thought?
>
> Thanks for any information,
>
> Peter

This is a b-i-g- subject, too big to answer in a NG post. Google for
the subject, or buy a book.

Colin