how to find the three corner of the triangle of the each frame of the video ?

Hai everybody, Actually, I have a video file which is the triangle particle flow. Now I want to know the 3 corner of the triangle in each frame of the video. Since the video has large number of frames It is very hard to analyse manually to find out the corner points.

I want to plot the corner A(x,y),B(x,y) and C(x,y) as function of time.

Herewith I have attached the video file.

So please help me for solving this problem.

vijay