Graphics Programs Reference
In-Depth Information
2
In the Save As text field, type
JPEG_ffffcc
, and then click Save. You now can select these settings
from the Preset drop-down menu at the top of the Optimize window.
Now that you have saved your settings, you will save your optimized image file.
3
In the Save for Web window, click Save. In the dialog box that appears, navigate to the advps10lessons
folder and in the File Name text field, type
advps1003_optimized
. Ensure that the Format menu is set
to Images Only and that the Settings menu is set to Default Settings. Click Save, then select File >
Close.
To test a file, click Done instead of Save. This keeps your settings and does not save the file.
Saving images as GIFs
GIF is a popular web format that has limitations in terms of color and appearance. This file format is
lossless, so the clarity of the image is not compromised by GIF compression. You can compress the file
size of a GIF by reducing the image's pixel dimensions and the number of indexed colors that it uses,
which makes GIF the best format for images with a lot of solid colors, such as logos and illustrations.
The compression algorithms for GIF files work best on large spans of color, thereby reducing the file size
when optimized. However, a photographic image or an illustration with a lot of tonal values will result in
a much larger file size than a same-sized image with solid colors.
The GIF format works best with images that have large spans of solid colors. In this example, an image with
a lot of tonal values are saved as a GIF with 32 colors.
When saving as a GIF, your image file can contain up to 256 indexed colors, but you should reduce the
number of colors to the minimum. You can reduce an image to four colors, but it requires testing to find
the best-looking file with the smallest file size.
You can animate GIF files and include transparent pixels to blend the image with different-colored back-
grounds. The pixels in a GIF image must be fully transparent or fully opaque, so you cannot fade the
transparency as with a PNG image, which is discussed later in this lesson.
In the following steps, you will open an image that contains multiple shades of solid color, and you will
save it with a transparent background. You will then animate the image.
You should use animations conservatively because many viewers do not like the distraction.
