An SWF is the output file produced by Adobe Flash. This is the content that users see when they visit a website that utilises Flash to deliver a dynamic navigational interface or Web content such as animations or video. The simplest way to change the play speed of SWF files is to change the frames-per-second setting inside of the Flash project file. Increasing or decreasing the number of frames per second changes the rate of playback, the smoothness of the animation, and the memory strain on the Internet server or computer that reproduces the SWF.
Double-click on the Flash project file that produced the SWF you want to change. These files usually have the same file name, but have the "FLA" file extension. In most cases, the FLA file is in the same folder as the SWF on your computer.
Locate the frame rate settings for the FLA. This is the blue number next to "FPS" directly under the timeline in the upper area of the work screen. This is the frames-per-second setting.
Click on the blue number to edit the frames-per-second setting for the project.
Input a larger number to increase the play speed of the resulting SWF or a smaller number to slow down the playback. The frames-per-second setting indicates the number of individual frames shown in 1 second of playback. The default settings use 12 frames per second. Increasing the number to 24 would cause the SWF to play twice as fast and decreasing the number to 6 would make the SWF play at half speed.
Press "Ctrl" and "Enter" simultaneously on your keyboard to update the SWF file with the new settings.
A higher FPS setting usually associates with smoother playback, but increases load time and system strain.