Well, black against black with barely any motion isn't going to do much with the Rotobrush tool. You are using the wrong tool. There are simply no discernible edges it can latch on to and synthesize the motion data required to detect foreground and background. You need to create conventional masks to isolate your subject.
1 person found this helpful
Mylenium is right; the RotoBrush is unlikely to work on that source footage.
But you're also using it wrong. You are not supposed to trace the outline of something with the RotoBrush. That is exactly NOT how to use it. It's not an intuitive tool. Read on how to use it here.
But, again, I wouldn't expect it to work on that footage.
Thank you for your response. I did exactly what you suggested and it worked with conventional masks to isolate the subject. Much appreciated my friend!!
My apologies for not using the Rotobrush correctly. I just applied masks to it and it seemed to do the trick good enough. Thanks again for your help and suggestions. Much appreciated! :-)