Incredible capture! They clearly could have taken out the Mini 4 Pro if they wished to. They appear more curious about checking out the little guy, than threatened by it. Likely juveniles? As others have noted, they attack from above, rather than...
Wow, you were lucky, their coloration shows that they are young birds, their chase was more curiosity than aggression, if your hit by a falcon, it will 98% of the time be from above.
Fantastic filming.