This is an archived tutorial from the kirupa.com legacy collection. It covers software that may no longer be available, but it is kept online because the ideas still hold up.
Flash is known for publishing animations that do not take up a lot of file space. The vector format of the Flash SWF file is ideal for the Web because it uses math instead of actual images to store animation elements. A 1 minute SWF will usually be smaller in file size than a 1 minute GIF image because of the use of math!
With all of the size reducing capabilities of Flash, you will still come across bloated animations on the Web. The animations that contain a BMP image of their background, the full soundtrack of Final Fantasy as the background music, and anything else the animators could get their hands on.
This tutorial will address how to reduce the file size for your movies. You will learn how to compress images, customize sound, use vectorized graphics, use fonts, and more.
Compressing
Images
A nice feature of Flash
is that images can be animated along with text and other
objects. What is not nice about Flash, is that the default
setting for optimizing and compressing images does not work
for all the images all the time. The following steps explain
how to optimize images individually in Flash instead of
using the global image compression setting found in the
Publish Settings window.

[ compression drop-down menu ]

[ size report: the image had a 98%
file size reduction after compression ]
The minor settings for images are often overlooked by many developers. Failing to set individual compression settings for images often creates images that are either inflated or blurry. Only by setting the compression setting for each image (provided there are only a few), can you easily judge the quality and make any necessary file size adjustments selectively.
Compressing
Sound
Just like you were able
to compress images individually, sounds can be compressed
individually as well.

[ compression drop-down menu ]

[ compressing an MP3 file ]
Two common misconceptions that people have are that converting a bitmap image into a vector would somehow result in a smaller file. While the file size may go down, most of the time the file size increases to a level larger than that of the original image. The following section will explain how to make sure vectorized images are optimized for the best size.
Optimizing
Vector Images
First of all, if you
don't know how to create a vector image, this section is of
little use to you. So, click the following link to learn how
to convert a bitmap image into a vector:
http://www.kirupa.com/developer/flash5/vector.asp
The following tips will help you to optimize vectorized graphics so that they take up as little space as possible:
![]()
[ the smooth and straighten buttons
]
- Select your vectorized bitmap. Go to Modify | Optimize. The Optimize Curves window will appear:
[ the optimize curves window ]
- You can optimize the curves in your images by modifying the settings found in the Optimize Curves window. Of course, dragging the bar to Maximum and checking the Use Multiple passes checkbox will produce the best result.
NOTE: it may take more than 3-10 minutes to optimize a vectorized image if you set the optimization settings to maximum and check the option for multiple passes.
Using Text
While you may not know
it, the text you use on your animations may take up more
space than the sounds and images combined! Here are some
tips to reducing file size using text.

[ the text options tab ]
From the Text options tab, you will see numerous buttons under the Embed fonts caption. Below is an explanation of what each option does:
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Embeds the actual font outline. The text will look blurry with this setting enabled. |
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Embeds the outline for only uppercase letters. |
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Embeds the outline for only lowercase letters. |
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Embeds the outline for only numbers. |
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Embeds the outline for punctuation marks. |
As you can tell, each of those buttons correspond to a method of embedding text. When the text is embedded, an actual shape outline of the text is displayed. Checking these boxes is the equivalent of breaking apart text. While you can selectively choose which types of text (numbers, punctuation, lowercase, etc.) gets embedded into the SWF file, the files size, nonetheless, increases. It is best to avoid embedding text.
This concludes this revision of this tutorial. This tutorial was written with input from several expert Flashers from the kirupa.com forums. I'd like to thank the following people who gave some input and tips about helping to reduce file size in Flash: thoriphes, eyezberg, suprabeener, and Mikeylzkt. You can see all of them on the forums by clicking the Message Board link below.
I hope the information helped. If you have any questions or comments, please don't hesitate to post them on the kirupa.com Forums. Just post your question and I, or our friendly forum helpers, will help answer it.
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