What would be the best (e.g. most compact) format for a "video" that is actually an audio track with a single static image the whole time? (example)
And if it was not one static image, but a slow slideshow (maybe 1 image every couple of minutes)?
One more case: What if it is a short clip (1-2 seconds), that itself is full quality (I think that means 25 FPS, right?), but is played in a continuous loop throughout the entire audio?