Sources of Raw Image Materials
Part of the GIMP is about digital image creation, but much more is
about digital image manipulation. One of the primary problems in any
project, then, is finding the necessary raw materials: the digital
images to be manipulated.
There are many sources for digital images. A scanner is one
possibility. However, some care must be exercised, because fair use
rules can be a little tricky concerning copyrights .
It is particularly recommended that caution be used when using an
image of a recognizable person or any trademarks or company logos.
These sorts of images are often aggressively protected, even for
noncommercial use.
Of course, scanning one's own photographs is an excellent source of
material. If you don't have ready access to a scanner, photo-CDs are
a relatively inexpensive way of having your photographs professionally
scanned and saved in a convenient storage medium. Digital cameras are
also excellent tools for getting the pictures you need. Many
good-quality, low-priced digital cameras are now available. A major
advantage of a digital camera is that photos can be taken and
immediately evaluated. Thus, if the photo doesn't quite have the
desired qualities, it can be taken again, until the right subject
matter is created. Several of the images used in this book were
obtained this way.
Nevertheless, it is often inconvenient or just impossible to
personally take photos of some subjects--pictures of frosty icebergs
at the South Pole, a Bengal tiger in its natural habitat, the space
shuttle in orbit. Most of us just can't go there to get the shot.
Let's not despair, though. There is a treasure-trove of free
photographic material on the Internet, and all of the above and much
more can be found with a little effort. The secret is that many
United States government web sites have no-copyright-assertion
policies. This means that most of the photos on these sites can be
freely used both commercially and noncommercially.
Examples of excellent sources of large, free image archives can be
found at web sites for the National Aeronautics and Space
Administration (NASA), the National Oceanic and Atmospheric
Administration (NOAA), and the U.S. Fish and Wildlife Service (FWS).
These all have terrific image libraries containing tens of thousands
of images of animals, plants, underwater life, space, planes, ships,
and so on. The following is a list of web sites that are the starting
points for exploring some of these image collections. Just remember
that there are some restrictions, and the responsibility of
ascertaining the copyright of each image remains with you. Make sure
you read the copyright claims on each site before using images found
there.
Much of the raw photographic image material used in this book comes
from three main sources. NASA has several excellent sites housing
image collections. Here are the three I made the most use
of:
https://www.nasa.gov/gallery/photo
https://images.jsc.nasa.gov
https://nix.nasa.gov
I have also made heavy use of the NOAA's main photo site,
which can be found at
https://www.photolib.noaa.gov
The U.S. FWS also has a terrific photo library located at
https://pictures.fws.gov
The convention used in this book for crediting photos taken from these
sites is to give the complete URL of the image the first time it
appears in the book. This not only credits the image source, but can
also be used by the reader to directly access the photo from the
Internet.
There are many more U.S. government services that provide some or all
of their imagery free to the public. The U.S. Navy and Air Force, the
Library of Congress, the U.S. Geological Service, and many more have
web sites with images free for public use. Although these sites offer
large, useful collections of images, it is sometimes frustrating
browsing their sites, trying to find the right image for a special
project. A solution is to download the entire site using
web-mirroring software. The images can then be extracted and placed
in a separate directory. This creates a personal image library that
is much easier to browse than it would be online.
There are several free web-mirroring programs available. The one I
use is called GetWeb , and its homepage is at https://www.enfin.com/getweb/index.html.
Figure
5
Figure 5:
Graphic Interface for Web Mirroring Software: GetWeb
 |
shows what the graphical user interface for GetWeb looks like. It is
fairly self-explanatory, with fields allowing the entry of the root
page's URL, descriptions of the types of files to be downloaded,
file-filtering mechanisms, and the directory to save the files to.
GetWeb downloads a web site to the specified local directory, while
maintaining the relative directory structure of the mirrored site. If
the root of the local directory is called MIRROR, a bash shell
script that can be used to cull all the JPEG image files might be:
#!/bin/bash
mkdir IMAGES
find MIRROR -name "*.jpg" -exec mv {} IMAGES \;
You would use the script by moving it to the directory
containing
MIRROR and running it there (it might be necessary to
make the script executable with the UNIX
chmod command). This
would produce the new directory named
IMAGES containing all the
JPEG files.
©2000 Gimp-Savvy.com
