Why does VirtualDub show so many frames per second?

Question

Video processing

I downloaded videos from YouTube in 720p and 1080p resolution, and when opened in VirtualDub, 720p video shows some sane number of frames, and 1080p shows some millions of frames. - in terms of about 30,000 frames per second. and if you then resave the video with full processing - that which is 720p is quickly saved - there are not very many frames obtained - and 1080p will be saved forever, because there are 30,000 frames in every second. what's wrong?
help