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Creating Images
There are many excellent commercial products for creating graphics
with Windows. They are broadly divided into two groups:
(1) painting programs and
(2) drawing programs.
Painting Programs and Drawing Programs
Programs in the first category build up an image by assigning a
color to every pixel of the screen that falls inside the boundaries
of the image.
Programs in the second category build up an image by assembling
lines, arcs, etc. that are considered by the program to be distinct
objects rather than just a set of unrelated pixels.
Paint programs are generally easier to learn to use, but drawing programs
can give higher quality results for many forms of graphics.
Some programs combine both painting and drawing
capabilities.
The Windows 95 accsessory
Paint
belongs to the first category; Freehand and
Illustrator are professional graphics level
examples of the second.
Native Formats for Saved Images
In many cases the programs save graphics images in their own "native" format
that is specific to that one program. It is normally wise
to save a version of the
image in this format since you may wish to modify it later. However,
in most instances, the native format for the graphics program cannot be used
directly for images to be displayed by Web browsers.
Exporting Other Image Formats
In addition to saving an image in native format, graphics programs
usually also give you the option of saving the image in a format that can
be used in other programs (but such saved files often cannot be further
modified by the program you used to create the image).
As we noted earlier, many graphics programs for Windows allow you to save
an image in BMP format (often by choosing "Save As" from the File menu and
selecting BMP format for the saved file, but this depends on the program).
Since you are then saving an image
for use by another program, outside of the one that created the image, the process
of saving a file in such a format is often referred to as "exporting" the image.
As we will now discuss, BMP format can be converted to the GIF and JPEG
formats that are most useful for Web images.
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