Hey Scoot,
[coments on bitmap vs. vector representation deleted]
> Gee... we're gonna use fuzzy logic to average the color of new pixtels.
> Sign me up for some of THAT. Not. Plus it's a PITA to get the proggie
> set JUST so.
There's no fuzzy logic involved. There's some math, and it helps a lot if you
know something about signal processing, but even without that it is easy to
understand: Since information (detail) cannot be created from scratch, the
most a program can do when sizing up an image is figuring out how the tones
change, and coloring the extra pixels according to that. For example, if you
have a black and a white pixels next to each other, and the resized image
needs to create a new pixel in the middle, the best the computer can do is
paint it grey. This would be "bicubic" in Photoshop. If you use "Nearest
neighbor", the computer picks the color that is closest to the new pixel, so
it will paint it either black or white. Suppose it picked white. Since now
you have two white pixels next to each other, you'll see a "box". This is
where pixellation comes from.
This explanation is valid for bitmap data. All photographs you see in a
computer are bitmaps.
The reason you can scale vector data: Suppose you have a picture of a square.
A _bitmap_ representation of this would be a big matrix of white pixels, with
a set of black pixels where the square is. A vector representation of that
same thing would be, for example, something like "square(10, 10, 20, 20)".
This is just an instruction that tells whatever program can read it how to
draw the image. As you see, the resolution at which that square is drawn is
independent from its representation. That's why in general you can scale
vector data without jagged edges.
> If this was so great why aren't lousy webcam shots "cleaned up" till one
> can see birthmarks
> the model's mother never knew existed?? Eh?
Lousy webcan shots are bitmaps. There's no way to create detail that is not
in the original. *IF* you had a "vector representation" of the model, and
that representation included the birthmarks that her mother doesn't know
about, you could get an image of said model at any resolution, complete with
every birthmark. Don't make plans though, since a vector representation of a
photograph is not a trivial task (I'd say it's one of the holy grails of
computer graphics, related to computer vision, image recognition, rendering,
etc). "Vector representations of photographs" are not at all mainstream, and
they are indeed not going to help you in the near future.
As a side note, "genuine fractals" does a kind of vector representation of a
bitmap, that lets you scale up an image with less distracting artifacts. Of
course, no information is created, but the existing info is interpreted in a
more efficient way (the program "detects", for example, a diagonal edge, so
it knows that it shouldn't draw a square staircase when scaling the image up)
> This isn't to start a pissin' contest over Photoshop. You like it, USE it.
> You know a
> no-brainer way to config it... SHARE it. I just haven't seen a whole lot in
> this program
> that goes above a 4 on the "Gee-Whiz" scale.
Photoshop doesn't need anyone's defense. There is little to say about
configuring it, too.
You have the program. I'd recommend you get a book on it, something with
practical examples, and read it and do the examples on your own. Really.
If you want to start on your own, make yourself a little white image. Draw
some black lines with the pencil (not the brush, try that later). Play around
resizing that image up and down, and see what happens. Pay attention at how
pixel values change. I'm sure you'll get the hang of it in no time.
You say "If you like it, USE it." I'll add: If you know it, you'll LIKE it.
Get that book. You won't regret it.
HTH,
j
PS: I don't know what DreamWorks program you're talking about. And we don't
use Crays, just PCs with Linux :-)
=====
--
Juan J. Buhler
http://www.jbuhler.com
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