Elephant Dreams test video

I recently found these sample videos for codec/decode testing and was
wondering if someone can give me more info on these files and how to
use them.

http://media.xiph.org/ED/


First I would like to know what is the frame rate needed for the
ED-360 and ED-1080 to be sync with the audio samples??

Second what tool (specific command) can I use to convert this sequence
of PNG files to raw YUV and to Theora??

thanks
Horacio