6 copyright: Brian Matherly
7 creator: Brian Matherly
14 Generate periodic synchronized audio blips and video flashes.
15 Blips are a 1kHz tone and last the duration of the flash frame.
21 The period between flashes in seconds.
30 The number of frames to offset the audio.
31 A positive number results in audio earlier than video.
32 An negative number results in audio later than video.