There was an app called Live Picture (I think) that worked on proxy images. Back in the 90s when no one had the horsepower to work on even medium sized digital files. I never saw that program in action.

I like the slickness of the interface in the video ... how the curves pallette can be resized by dragging it. Would be cool if it showed a histogram in the background, or at least clipping points.

Does it work with layers?