Play a video with transparent background in ios

I need help in playing a Transparent Video in VideoPlayback sample for iOS.
I am ok with either of 2-options:
1- Playing a Transparent/Alpha channel video in VideoPlayback.
OR,
2- Playing a Video with Green background and then remove Green color background in OpenGL using Shaders or something else.

Please let me know if you can help me with any code samples or any hints to solve this problem.

Regards,
Jittender