Dummass newbie? Increasing resolution

[hank]

I have an existing .jpg image that I want to "improve." Is there a
graceful way to convert each pixel into either 4 or 16 pixels? (The
color depth thing comes later.) If not feasible with GIMP, are there
other modalities (e.g. hex editor)?

Hank

[Nick Lamb]

Image -> Scale Image : Ratio 2.0 (or 4.0)

I do hope you have a good reason for wanting to do this, you won't find
any "lost" detail that way.

Nick.

[Carey Bunks]

[Posted and mailed]

In article <3A56A462...@aa.net>,

Hi Hank,

There's a world of difference between improving an image and changing
its resolution. If you want a graceful way to increase the number
of pixels in your image, try "<Image>File/Image/Scale Image". This
increases the number of pixels while using a reasonable interpolation
algorithm. You can find more about it in section 2.6.2 of this
document:

http://gimp-savvy.com/BOOK/index.html?node32.html

Otherwise, for specifically improving an image, I recommend you take a
look at this chapter of Grokking the GIMP:

http://gimp-savvy.com/BOOK/index.html?node59.html

Hope this helps.

Carey

================================
Carey Bunks
author of "Grokking the GIMP"
creator of http://Gimp-Savvy.com
================================

[James Waldby]

The commercial product "Genuine Fractals", a plug-in for
Photoshop, is supposed to work well for upsizing.

For gimp, select cubic interpolation via
File, Preferences, Environment, Cubic, and (optionally) Save.
The few images I've upsized looked ok with just cubic
interpolation, without any blur or sharpen steps afterwards.

[Nevit & Ilham]

Hi,

I finished reading GTG last week. I want to express my thanks to author
of this book. It is a great reference.

Nevit

[hank]

Thanks! I'm hoping to generate detail not there now.

[Jeff Epler]

On Sun, 07 Jan 2001 03:51:26 +0000, hank
<ha...@aa.net> wrote:
>Thanks! I'm hoping to generate detail not there now.

The "resynthesizer" plug-in has a script-fu to do this, but be warned.
The produced details look more like oil paintings when the magnification
is high, and the runtime and memory consumption are astronomical. On a
PII-350, it took about a week to double an image which was something
like 640x480 in the input. I was going to do a 1280x1024 input image,
but in that case the memory consumption climbed to approximately 500 megs.

You might get acceptable results by working with part of your image in a
separate buffer, using regular interpolation (image->scale) for the rest,
and then using layers to composite the two together. I haven't tried this
technique.

image->scale and then a sharpen operation such as unsharp mask is the
more traditional way to enlarge an image and then add false detail. Many of
my friends found this preferable to the output from "resynthesizer".

Jeff

[Reed Hedges]

In article <slrn95h2v9...@potty.housenet>, Jeff Epler wrote:
>The "resynthesizer" plug-in has a script-fu to do this, but be warned.
>The produced details look more like oil paintings when the magnification
>is high, and the runtime and memory consumption are astronomical. On a
>PII-350, it took about a week to double an image which was something
>like 640x480 in the input. I was going to do a 1280x1024 input image,
>but in that case the memory consumption climbed to approximately 500 megs.

wow! i scale images much larger than that on my 350 all the time!
(64mb ram). what's up with that? or are you talking about the script-fu
script? i've found script-fu's to be frustratingly slow. is this a
common problem, and area of improvement for the gimp?

rh

[BlackJack]

The resynthesizer plugin doesn't simply scale the image. The scaling
itself is done by the gimp scaling function. But it analyses the
picture and then tries to "invent" details to make the image looking
more "natural" than the normal scaling.

And the plugin can be used for other things too like automatically cut
out something like it never was there and filling up the space with
graphics that are looking similar to the parts surrounding the cut.

And analysing the picture is pretty time and memory consuming.

Ciao,
Marc 'BlackJack' Rintsch

[Philip Bartol]

BlackJack wrote:

>The resynthesizer plugin doesn't simply scale the image. The scaling
>itself is done by the gimp scaling function. But it analyses the
>picture and then tries to "invent" details to make the image looking
>more "natural" than the normal scaling.

Sigh.... till I get my Hard disk upgrade I guess I'm stuck with Windows...

[kicking ground] Linux has all the fun....

PHIL