The video is low quality as the video was uploaded in the quality used by elf your self.

Question and Answers

Q: What is that grey bar at the bottom?
A:That tells the computer what frame it's on. The flashing squares are the binary representation of the number next to it. Every white square is a 1 and a black square is 0. I don't know exactly what they are used for but I guess its something to do with making sure the faces are in the right position on each frame.

Q: How did you get these?
A: I found them using the google chrome inspect element network log tab. When a video is played you see a request that looks like this "hip_hop_1h_1280_coded.mp4" Then just open the request URL "https://elfyourself.oddcast.com/ccs6/..." Then download it.

Q: How does the website know were to place the faces?
A: A .xml file contains all the head position, rotation and scale for every couple of frames.

If you have any other question ask in the comments and I'll try to reply.

0:00 Office Party
1:09 CATS!
2:25 OH HANUKKA
4:33 Santa's Workshop
5:44 House Party
6:46 Secret Santa
12:12 Breakin
14:24 Elf Spanol
16:37 Charleston
17:39 Sleighride
18:42 Dance Off
19:54 Hip Hop Shop
21:01 Wonderland
22:14 Feliz navidad
23:22 Mashup