Pan & Zoom of (large) still images

Hi!

I'm currently experimenting with P&Z of large (Panorama) Images. One issue there is that small features (distant trees, pebbles etc.) produce an annoying flicker when moving the FOV. I found an old post that suggested some blur, and especially to apply it before the panning. I had tried (normal) blur after the pan, which also seems to work. I noticed that applying the blur before is darn slow... The thing is, I don't really understand where this comes from. In principle I should have one image, and from that I cut out different parts. But then there should be no flicker - the pixel values should always be the same for a feature. So obviously the image is rescaled anew for every single frame, and seemingly with different parameters

Nevertheless, some questions: How are you doing this (if at all)? Is there a common sense how to properly get rid of this flicker?

Is there somewhere a description how scaling is done at all? The P&Z controls seem to refer to an image size of 100% when the image is scaled so that is completely fits in the FOV of the movie. I assume that it is not first scaled to fit and then again magnified if one wants the large image.

To what image is the blur applied? E.g., I import an image of 4870x3130 px into a 720p project and apply a square blur filter with kernel 1, followed by a P&Z that pans vertically at 'maximum' width. This means it's a 1280x822 image (P&Z claims it's at 114.17% size), and I have 102px to pan. But on hat image does the kernel of blur work? On the full image? On a 100% image? Things can be quite confusing at times (and I'm afraid my posting suffers from the same deficiency...)
So any input is welcome!