The Speech API extension lets you convert Strings to voice files and vice versa without any annoying mic activities. the extension will work fully in the background. if you have downloaded language packages from Google, the extension will work with no internet connection required and if offline packages are not available, it will automatically load the voice file from internet.
— myflashlab.com (@myflashlab)August 16, 2015
Complete tutorial with full source code:
Interactive video with 4 corner pin Motion-tracking (After effects + Flash)