Looks merely like a quick sequence of photos and then a white flash...
- Change your project settings to 32 bit
- Start a new comp that is only about 8 frames long.
- Add a full frame rectangular gradient with a white to off white radial gradient fill by setting up the gradient fill first, turning off the stroke, then double clicking the Rectangle Shape tool with no other layers selected in the timeline
- Trim the shape layer to about 8 frames long
- Set keyframes for opacity from 0 at the in point to 100 at the 3rd frame and then 0 at the out point
- Change the blend mode to ADD
- Find an audio clip of a shutter click and add it to your project and then sync it up with the flash you have created
- Nest this "flash" comp in your comp with the footage
- Collapse transformations or change the nested comp's blend mode to add
- To your nested comp add Effect > Color Correction > Exposure and animate the values if needed to emphasize the flash Throw in Hue and Saturation to add color to the flash if needed
That should do it. Now just position your nested flash comp where you want the flashes. That's all there is to it.
That is cool... I will try this when I get back home from my vacation!! Thanks