On Wed, 21 Apr 2004 00:03:36 +0100 (BST)
ard_at_p850ug1.demon.co.uk (Tony Duell) wrote:
> > Moreover, 3.1M pixels in the camera aren't 3.1M pixels in the final
> > image. It depends how they're used, but in the camera, you
> > typically need three pixels, one for each of R, G, and B, to get one
> > RGB pixel in the image. Some techniques use even more (the Bayer
> > algorithm uses 4).
> Argh!. You mean they fiddle the figures? I'd assumed that a 'pixel'
> was an RGB triad, not a third of one. So you mean you may only get 1
> million points in the image from a 3.1M pixel camera?
Yes. E.g. with Bayer you have four sub-pixel per color pixel:
R G
G B
So you get 640 x 480 = ca. 0.3 M "true" color pixels with a 1280 x 960
"Mega pixel" sesor. The image processing firmware of the camera
interpolates this later to 1280 x 960 RGB pixels.
--
tsch??,
Jochen
Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/
Received on Wed Apr 21 2004 - 02:50:53 BST