Gigapixel does a ridiculously good job. 800px width images to 1000mm width. Photographer/artist had applied filters in some app, and only had 150kb files. I was sure it would fail, but it was like Gigapixel had a firm understanding of the effects the filters were designed for.
The moment someone can see (online, in person) and capture an image, control of the image is almost gone.
Flip side is that when someone has precious photos that only exist on instagram, we can make prints for them.