How to switch between frames with in a video file

[gurusoldier]

Consider that i have two streams of same video file. one stream is watermarked with say 0 and another stream watermarked with 1. Depending on a key I have to switch between these two streams. How should I embed switching point within the frames?

EXAMPLE:


In the figure above the KEY VALUE is 010. The key value indicates which watermarked frame is to be selected. So in the example shown, the first frame in the output is from STREAM1 (watermark 0), Second frame is from STREAM2 (watermark 1) and the third frame is from STREAM1 (watermark 0) and so on.

Thanks in advance