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Flash Player TechNote
How to make a Flash movie with a transparent background
The background of a Flash movie can be set to transparent. This allows the background color or image of the HTML page that contains the Flash movie to show through and allows the layering of Flash content with DHTML content.
The following browsers currently support windowless mode:
Windows and Mac OS X
Internet Explorer 3 or higher (Windows)
Internet Explorer 5.1* and 5.2* (Macintosh)
Netscape 7.0*
Mozilla 1.0 or higher*
AOL*
CompuServe*
* Macromedia Flash Player version 6,0,65,0 (Windows) or 6,0,67,0 (Macintosh) or higher required for this feature.
Note: Mac Classic is not supported for this feature. Transparent backgrounds are also not possible in a Flash standalone projector.
Note: If windowless mode is used, performance can be affected to some degree. If fastest performance is a top priority, you may consider other design options.
Preparing the HTML page to make the Flash movie transparent
Three methods of creating an HTML page with the correct code are outlined below.
Publishing from Flash
The HTML for a Flash movie can be created using the Publish Settings feature in Flash. The Publish Settings dialog box provides an option to affect the WMODE setting. The options selected in the Publish Settings will be added to the HTML source code automatically:
Choose File > Publish Settings. Select the HTML tab.
Choose "Transparent" in the WMODE setting to make the Flash movie's background disappear in browsers which support this feature.
Publish the document.
Using Dreamweaver
Follow the below steps, and Dreamweaver will insert the correct HTML code automatically.
In Dreamweaver, insert the Flash movie into an HTML page.
Select the Flash movie in the Design View.
In the Properties panel, choose Parameters.
For the Parameter, enter "wmode" (without quotes). For the Value, enter "transparent".
Save the document. The HTML page is complete.
View a demonstration of these steps.
Editing HTML code manually
To edit an existing HTML page, add the WMODE parameters to the HTML code.
Add the following parameter to the OBJECT tag:
<param name="wmode" value="transparent">
Add the following parameter to the EMBED tag: wmode="transparent"