How to protect SWF files from decompiler?

Flash SWF files contain your important Intellectual Property, but once they are on the web and available to the public, anyone can download your SWF file, decompile it with a Flash decompiler tool, peek at your Actionscripts, steal your images, sounds, buttons and animations. The crackers can even convert your SWF file to a FLA source file, modify and redistribute it as it's their own.

This tutorial will guide you how to protect SWF from decompiler with SWFProtection.

What You Need:

SWFProtection: The software comes with a free trial, so you can check it out before you buy it. You may download the trial version at http://www.swfprotection.com/download.html.

SWFProtection stops all Flash decompilers, thus helps you protect your valuable design, hard working and intellectual properties from being stolen. The program uses a new capability of Flash 9 and Actionscript 3. It converts your whole SWF file to binary data, then encrypt the data and embed it into a new SWF file. In this way, all contents in the SWF file, including Actionscripts, images, sounds and animations will be protected. The program enhances the encryption further with Actionscript obfuscation.

The built-in domain locking feature can disable viewing SWF file from local computer and only allow SWF files being hosted on specified domains, so the SWF file will only work on your own website. If they are downloaded, they will refuse to play and display a warning message or just render as useless.

Step 1:

Download and install SWFProtection at http://www.swfprotection.com/download.html. Launch the software, click the button "Add File", browse the SWF files need for protection, add them to the file list.

Step 2:

Click the "Domain Lock" tab, check the options "Disable viewing SWF files from local hard disk" and "Only allow SWF files hosted on domains", then click button "Add", and enter your website domain name. If you want to display some warning message when someone tries to view your SWF file on local computer or upload it to his or her website, you can check the option "When domain is incorrect" -> "Display message", then enter the HTML formatted text in the input box. Hyperlinks are supported in the warning text.

Step 3:

Click the "Output" tab, define how to rename and where to save the protected SWF files.

Step 4:

Click the button "Protect". And congratulations! You have successfully protect the SWF files. In a typical Flash decompiler, the protected SWF file will show as following.

The following Flash SWF file is protected with SWFProtection, you may download it and have a test of the protection.