How does Icaros 'choose' the thumbnail that it displays

[PeterProg]

I've had good success with Icaros in generating thumbnails for many of my files that previously had no cover, or any other image, associated with them.

Just curious though, for any given, say, mkv file, how does Icaros 'choose' the thumbnail? Is it always 'x' seconds into the file, or is there some other thumbnail selection criteria that the program uses?

[johns0]

It's just some seconds in the video.

[PeterProg]

Cheers - good to know.