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If the flash-based viewers in sites like Scribd, etc. can display books like a PDF version of the book, why is it not possible to convert the same flash stream of data back to PDF?

One (very, very) naive method to implement this would be to:
1. Capture screenshots of the content displayed continuously.
2. Run some kind of OCR software on the captured screenshots.
3. Splice the screenshots together to get a meaningful PDF.

I am sure there are super-uber ways to do this but I just wanted to make my intent understood in simple terms.

And before someone goes all-out guns in the comments, raising issues like the illegality of doing it, and stuff like DRM, I just want to know the concepts behind why it is not possible for this to be implemented.

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The fact that you can convert X to Y does not mean that converting Y to X is easy, or even possible. Take C++ code for example, you can "convert it" into an executable file using a compiler+linker etc, however it is in general not possible to convert the executable file back to C++ code. –  yms Oct 9 '12 at 17:38
But if a guy can sit down and take n number of screenshots of x number of pages in an flash-based book viewer and splice them together and run an OCR software to extract data from the images into text form , why can't a script or program? –  Arpith Oct 9 '12 at 17:52
I am not saying that you cannot do that, and you could indeed "script it", but that will not give you the original PDF, and depending on the viewer it might not be 100% feasible. You may need to scroll a page and such, and I am not sure that the flash player will allow that kind of interaction with its hosting application. –  yms Oct 9 '12 at 17:59

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