Video File Types

What file types does dophin accept i.e. video and audio file types?

Also I am in the process of converting my html site over to dolphin, and it presently has more than 200 gig of files which as you can imagine is thousands of files. Do I need to reupload all these files one at a time, or is there a way to insert them into a directory and have dolphin automatically identify them? Any suggestions or instructions. Anything will be helpful and could save months of work. Thanks in advance for your expertice and help!