I put a VHS tape in my VCR, and at a certain point when it changes from static to picture, the video is black and white for 2 seconds then gains colour. I fastforwarded the VHS tape and rewinded it. Then I played it up to that point again, this time, there was purple and green, with some colour, then colour. Because there is colour for one more second on the 2nd attempt, I want to copy the frames from that and replace it in the original video. How can I do that?