in Tutorials

New Video Tutorial on Ethical SWF Decompiling

I just finished uploading a new tutorial to gotoAndLearn() which shows you how to use SWF decompiling as a learning tool to see what Flash is doing behind the scenes to your timeline code. Some people think that the words ethical and decompiling have no business being used together in the same sentence but I believe otherwise. It is obvious that you should not steal assets or code directly and if you do, you will more than likely get caught and be exposed. But decompiling your own work can be a great way to recover lost FLA files. I have saved my ass numerous times using decompilers! There are many good decompilers out there but my favorite is Sothink and it is the one I demo in this tutorial.

Enjoy the tutorial!

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  1. Basically its like the view source yes.

    As long you don’t steal sounds, certain animations, use certain lines to hack a server etc, etc, I am fine with it.
    It’s an excellent way to broaden your learning curve.
    And as Lee mentions: No more missing fla’s.


  2. There’s always the option to encrypt your SWF files if you want them to be protected. Apparently Amayeta are releasing AS3 encrypting software soon.

    Anyways, nice tutorial Mr B

  3. I’ve never actually heard someone being against decompilers for Flash. Sometimes you can’t find a source file or tutorial to do a piece of Flash work and seeing how someone else did it can give you ideas on how to do it yourself.

    @ Luís:
    Check out these two links:

    That’ll give you all the information you need to contact their hosting provider. Say that you’ve contacted the site repeatedly and they refuse to take down the files. Depending on how reputable they are they will take action on your behalf. Especially if you threaten any sort of legal action.

  4. I had never seen how a simple frame action is, in the end, packaged into a document class in the swf. I think the ethical question is just a tangent to your demonstration. Thanks for the tutorial.

  5. I have used before this decompiler, to recover lost fla files. After decompiling the file doesnt look as it was in the original fla, but it can save you of lots of trouble and re doing stuff.
    Usually I use the Amayeta encryption tool.

    Its a shame that people steal assets and contents using this tools.

    Paulo Moreira

  6. I have wondered for years why former Macromedia and now Adobe never bothered to build any kind of code obfuscation or resource-protection into Flash. Releasing tutorials about how to decompile swf is same as teaching people how to rob a bank just because “its interesting to see how things work” and “in case you own a bank and you lost the keys at least you can get back in”.

    Hey, what is this thing we see in Flash Publish settings? “Protect From Import option: Prevents others from importing a SWF file and converting it back into a FLA document. Lets you use password protection with your Flash SWF file.” Obviously a straight lie, as we have seen from this tutorial, it does no prevent others from importing a swf file and converting it back into a fla document. Maybe its a joke from developers behind Flash, you know, lets put in something that does not actually do anything.

    Lots of Flash content is being stolen using the decompilers and instead of helping developers who create content you create tutorial to educate even more hackers. I mean why? Do you hate Flash that much?

  7. I think some people really missed the point of this tutorial. Personally, being a Flash developer, I don’t want my stuff ripped for profit, but opening it to see what’s under the hood is not really a problem for me.

    In response to the “Protect from import” option in Publish Settings. That is actually to disallow Flash to open an SWF and get the assets out. Of course Sothink and others have managed to get around this.

    On a similar note, there are tool to obfuscate ActionScript, but its not right to link to outside resources in a comment, so just do a quick Google search if your interested.

    Great video Lee, very informative for other Flash users.

  8. Interesting discussion! Personally I must admit that decompilers has helped me learn Flash better than most books and tutorials I have seen, but I dont steal though!
    Often you don’t know what you are looking for in tutorials, and you just bounce into stuff using decompilers that teaches you what you didn’t know you should know!!!

    I don’t think stealing code pieces is cool at all and nobody should do it, but learning how to do stuff and looking at different ways to build a Flash site only improves the average Flash developer’s skills, which in the end should help Flash to gain a better reputation and result in better applications etc.

    I admit that this tutorial is a bit redundant though, cause you don’t have to be a genius to figure out how to use decompilers, and this might just result in many new “developers” taking the easy way – I don’t know!

    But anyway, if you are afraid of people stealing your code, just do something about it – encrypt or kick their ass :-) I don’t have a problem with people finding inspiration and techniques in my files, I love that the Flash community is very openminded and everybody is helping everybody (forum, tutorial etc.) – that’s how a lot of us got to where we are!

  9. I hired someone to create special graphics using flash for my portal. He stayed on the project, and on my payrole for over a year and a half. He also managed my server and one day i discovered that he was entering my mail accounts. I fired him on the spot and asked that he supply me with all the source files (fla), and he denied me them. I have 160 flash files and no codes. Its a problem, because i can’t continue the project and the developments i need to implement. What can i do. Oh BTW, he used to incript everything. The bast….d!! Can the “Sothink” program resolve my problem? Can someone help me?

  10. All forms of media are exposed to copyright violation, Flash content is no different. MP3’s did not kill the music industry, neither will decompilers kill the web development industry.

    There is a steep learning curve involved in Flash authoring and only by examining real-world applications can newcomers to the field hope to learn new skills.

    It wouldn’t surprise me if half the people whining about decompilers were out there making big bucks in web development using cracked Adobe software. Which is the bigger crime?!

    For me, being overly protective of your work goes against the general ethos of web development and the internet in general. The net is about sharing ideas and communication. Of course there are unscrupulous people out there who will just plain plagiarize material but that’s human nature. Let’s not try and shut the door to the many by the actions of a few.

    Lee – keep up the great work, you are a fine example of the openness and sharing of ideas to which I refer.

  11. I use it for learning, recently in a forum I was told it was a “no no”, and given the example that it was like taking a car for a ride without permission.

    I do it to learn, no to copy. I look at it and understand how people work. The authors still have that advantage of being the ones that thought of that, you cannot steal that.

    So if you are not going around taking assets and pieces of code and claiming them yours! I think you are on the ethical side