The swf_openfile() function opens a new file named filename with a width of width and a height of height a frame rate of framerate and background with a red color of r a green color of g and a blue color of b.
The swf_openfile() must be the first function you call, otherwise your script will cause a segfault. If you want to send your output to the screen make the filename: "php://stdout" (support for this is in 4.0.1 and up).