Control sampling rate

[Arsakes]

I would like to use this tool to extract some frames from image to train deep learning system.
The issue i have is too many similar frames generated.
Would it be possible to set constant sampling rate for video?
I.e show and annotate only two frames per second?

[Peratham]

I think we can change the config in line 180 from https://github.com/dbolkensteyn/vatic.js/blob/master/index.html.