How does screentoaster.com capture your computer screen from the browser?

Question

How does http://www.screentoaster.com capture a computer screen from a browser using Java Applet? Any suggestion or a lead in how to accomplish this? Is there other way to do using using different technology such as Flash?

Answer 1

I haven't tried it (I don't want to risk it!!!), but the indications are that it screen toaster uses a signed applet, and you have to explicitly accept a certificate (which gets added to your browser's trusted cert store) to enable the applet to break out of the normal Java security sandbox. (I'm also taking your word for it that it does use an applet ...)

I would hope that other methods of capturing the user's screen via a web-browser are similarly protected.

I would also like to hope that most users are not crazy enough to install random browser plugins or accept random certificates. But sadly, this is not true.

This whole idea strikes me as being very risky. What is to stop the Screen Toaster guys from taking their own copy of what is on your screen, installing a key-logger, ferreting around for sensitive files, installing a rootkit, etc? And assuming that they are entirely honest, how do you know that their applet doesn't have a security flaw that could be exploited by someone else to do the same thing?

Answer 2

You can do it with just 5 lines of code.

1 . Create one rectangle representing screen. 2 . Create one BufferedImage to store image of the screen. 3 . Take snapshot using new Robot().createSnapshot() method. 4 . Save the bufferedImage in file.

Robot class is part of java.awt package

You can see more detail in the below link.

http://java.sun.com/j2se/1.4.2/docs/api/java/awt/Robot.html