The first idea is of course not to reinvent the wheel and search for an already-made solution. I had to find a really good way to extract information from a SWF file. I had two trivial ways to go : (a) find an already-made SWF Header Extractor, or (b) work at the binary level.
At first, of course, I turned to the PHP documentation (http://www.php.net/manual/en/) and found out the LibSWF and Ming libraries as candidates.
Of course, the code is provided for his solution, and it's actually quite simple. The class does the hard work of mapping out the data from the Flash file's header. All he needed to do was to reference that value in the result under the 'fps' array key.