1. Resizing a image
Hello,
Does any1 know of a good way to resize an image?
I am using a very large image which I want to fill the screen at the
beginning, then the user would be able to zoom in on specific bits.
2. Re: Resizing a image
On Thu, 19 Nov 1998, Thomas Parslow wrote:
> Hello,
> Does any1 know of a good way to resize an image?
> I am using a very large image which I want to fill the screen at the
> beginning, then the user would be able to zoom in on specific bits.
>
Probably the best way to do it is found in most of the older paint
programs like Neopaint. What they do is scale up a segment bordered by the
mouse pointer by multiplying a factor. For example, if you want to zoom in
on a segment in your picture by a factor of 4, a red pixel in that segment
would end up filling 4 pixel positions in your zoomed up view. The problem
with this approach is that the area being magnified would appear coarse
around the edges.
David Gay
http://www.geocities.com/SiliconValley/Vista/4346
A Beginner's Guide To Euphoria
3. Re: Resizing a image
Thomas Parslow wrote:
>
> Hello,
> Does any1 know of a good way to resize an image?
> I am using a very large image which I want to fill the screen at the
> beginning, then the user would be able to zoom in on specific bits.
try jiri's scale.e
i've used it/tinkered with it, and it works rather fast,
with very little image degredation...
there is also some libraries/utilities (2 or 3 i think)
that 'zoom under mouse' in the archive as well...
scale.e should handily solve your problem of an image being
too large or small for the screen...
the problem of selecting a part of the image and zooming in
on it can be a little trickier...
what you can do is save the highlighted section of the
screen (the area the user wishes zoomed) to an 'image'
in memory... by image i mean a 2d sequence of sequences...
you could then throw that picture segment/selection image
to the scale routine and let scale zoom that for you and
then simply display that new zoomed image on the screen...
hope this helps--Hawke'
4. Re: Resizing a image
- Posted by Ralf Nieuwenhuijsen <nieuwen at XS4ALL.NL>
Nov 19, 1998
-
Last edited Nov 20, 1998
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charset="iso-8859-1"
>Hello,
>Does any1 know of a good way to resize an image?
>I am using a very large image which I want to fill the screen at the
>beginning, then the user would be able to zoom in on specific bits.
Well, there are two options, you either:
1) try to use the machine code in texture demo by Pete, but it is not
stable, a CW-error every now and then is likely.
2) Use the more euphoric way, and use Jiri's fast 100% euphoria routines,
and since the file is *so* small, ive attached it.
Hope this helps you..
Ralf
------=_NextPart_000_000C_01BE13FC.26BD9E80
name="Scale.e"
Content-Transfer-Encoding: quoted-printable
5. Re: Resizing a image
Thomas Parslow wrote:
> Hello,
> Does any1 know of a good way to resize an image?
> I am using a very large image which I want to fill the screen at the
> beginning, then the user would be able to zoom in on specific bits.
*last second addendum to my last post*
i fergot to mention something, a pitfall that
i often forget... (as most have noticed by now,
my memory is burnt... a result of reading a C
program once out of curiousity :)
when (if?) you use scale.e to make the image
fit onto the screen... try to remember to keep
the actual image at its full size and splendor
in memory... it would be better, as opposed to my
prior post, to keep the original image in a virtual
screen if possible, and zoom in from *that* (after
converting to whatever format scale.e wants)...
this will contradict the (easier) method in my
prior post, and creates a problem, but solves one
too...
the problem solved is repetitive image degredation as
you are always starting with the most detailed picture
possible...
the problem created is that once you take the original
image, scale it, and place it onto the screen, and then
allow the user to select a segment of the image they
want zoomed, your offsets will be all wrong...
the solution to that problem (one i can think of at least)
would be:
in the beginning, load your picture to a virtual screen,
create a temp copy in the format scale.e wants, and
scale the temp copy to a specific divisor that will allow
the image to fit onto the screen, but not necessarily
use the entire screen...
hang onto that divisor...
when the user selects a portion/segment they want zoomed,
multiply the aforementioned divisor to the coordinates
of the selection, and use those new multiplied coordinates
to select from the main virtual picture screen.
copy this new 'offset' area of the main picture to a holding
place, convert to the scale.e format, and size
that to fit the screen (or what ever zoom factor they want
to be applied to *their* segment)
this is a little cumbersome, but ensures a relatively high
zoom image quality...
--Hawke'
6. Re: Resizing a image
Thanks
--PatRat (Thomas Parslow)
-- ()___()
-- (o o)
-- =\O/=
-- Rat Software
-- http://free.prohosting.com/~rats/ratsoft/
