Re: [PLUG] which image transfer format?

[Kevin Brosius <kbrosius@kns.com>]

Jeff Abrahamson wrote:
> 
> On Tue, Oct 15, 2002 at 03:41:18PM -0400, Jeff Weisberg wrote:
> > [2] the real world is not 24 bit color
> 
> Actually, neither is your digital camera, unless maybe it's extremely
> high end. Most digital cameras have eight bit CCD's with color masks
> over them, so, essentially, one pixel is 8 bit red, the next 8 bit
> green, the next 8 bit blue, repeat. (In practice, it may use a
> different color space, and so forth.)

Umm... In computer graphics, 24 bit color is considered 8 bits for each
of RGB, right?  What am I missing here?

Oh, I see, you're referring to the practice of only storing one color
plane _per_ pixel on digital cameras.  That doesn't really make them 8
bit color cameras though.  They still have 24 bits of color depth.  Just
1/3 the resolution (width x height), right?

> 
> The act of saving to the card, which typically takes a second or two,
> involves something like 100 operations per pixel, and is mostly about
> interpolating colors. This is why digital photos of sunrises or
> forests, where everything is essentially shades of the same color,
> usually look splotchy. It turns out to be a very good approximation
> for most things we take pictures of, though.
> 
> This is one of the advantages of technologies like X3
> <http://www.foveon.com/>, which do capture 24 bit color and so get to
> skip the time and (energy) expense of interpolation. In the case of
> X3, they also do it in CMOS, which is lower power than CCD's.
> 

-- 
Kevin Brosius
_________________________________________________________________________
Philadelphia Linux Users Group        --       http://www.phillylinux.org
Announcements - http://lists.netisland.net/mailman/listinfo/plug-announce
General Discussion  --   http://lists.netisland.net/mailman/listinfo/plug