Green screen flickers after encoding

So I recorded gameplay and editted in after effects

then I encoded this with media encoder (H.264, since AVI was too huge. original video was 1 gb and encoded avi video was 24 gb. what the hell??)

then the output was completely horrible.

green screen is flickering .

I upload the video that wil help you guys understand this problem

This video was recorded after the encoded one

tried QuickTime, AVI and mp4(H.264)

but QuickTime and AVI was unable to see. It just keep stopping and playing.

To watch vid's 10 secs I must wait for 1 minute

Tried turning off Mercury GPU Acceleration(OpenCL)

What Should I do???