How to make an image file flicker in a video? (stars twinkling)

Question

I have an image file (jpg, 4K resolution) which is a bunch of stars in the night sky. The image looks good when composited into a video clip, but the stars don't move or twinkle at all.

How can I make the stars twinkle? (I tried searching for a star-twinkling effect, and I would accept one if such a thing exists, but what I'm really interested in here is the compositing problem of taking a static image and then animating it a bit.)

1. Different parts of the image should flicker/twinkle at random (do not do the whole image all at once, because all the stars in the night sky don't shimmer in the same way at the same time)
2. I don't have time to keyframe every single star in the night sky.

I'm using DaVinci Resolve 12.5 on Windows, but I also have access to a Mac with Final Cut Pro X and Motion.

What I have tried

I tried increasing the noise in the video, then setting the blending mode for the stars image to screen. This makes it look like there is some movement in the shot, but it doesn't add twinkling.

Also, Resolve has three effects: "Waviness," "Vortex," and "Ripples." I tried keyframing various parameters to introduce some movement/flickering into the shot.

"Waviness" moves the sky itself, and even with all the parameters set to the smallest values it moves too much.

"Vortex" adds some whirlpool-like movement.

"Ripples" adds a shooting-star effect, which is cool, but not exactly what I'm looking for.

Answer 1

Create 10 copies of your star field image. In an image-editing program (like Photoshop or GIMP), open the first image. Pick 10 stars at random, and make them darker/dimmer. Save that image. Open the next image. Pick 10 different stars and make them dimmer. Do that for all of your images. In your video editor, cycle through the images, about 3/4 second each, dissolving from one to the next.