I started out as a photographer. For years in Asia I was chasing the "decisive moment" in a still picture, that moment I would chose when everything lined up perfectly, the light, the angle, the eyes, the form, the motion -- in that micro-second it all came together just as I clicked the shutter. If I were lucky I got the exposure and focus right. (But I never knew until I developed the film later.)
I've also done a small bit of filmmaking and videoing. Different camera, different mode. Forget the decisive moment, you are searching for streams and flows. Many times I wished I was videoing when I had a still camera. Is there a way to do both?
Why not just digitally "film" a scene and then take perfectly crisp stills from the "footage" to get the best of both worlds? Then you could take a decisive hour's worth of motion and then later pick through it to retrieve the best stills. You would be working with the advantage of hindsight, something you don't have in the field or real life. Making a decisive moment image will be much easier; you don't just have to be lucky.
Until now this dream has not been possible technically. The extracted stills were never sharp or rich enough to stand on their own. But a new camera from Canon makes it practical now. Advances in lenses, sensors and storage mean that you can "film" a scene and then extract very crisp, well exposed, information rich still images. Watch this video for a introduction.
The distinction (what was left of it) between still images and cinematic images is gone. As this technology continues to shrink and improve, eventually moving to your phone, it will change what we think of as photography -- including cinematography. Even though I spent many years aiming for that elusive moment, I welcome the disruption.