hello, If this is in the wrong category perhaps somebody can move it ?

I try to manipulate an image.

"zoom" in on it by cutting out a width from it.

each new image is proportionally smaller ( or bigger ) by the same amount

small=sqrt((big^2)*(1-p)^f)

where f is the next progression (frame) and p is the proportion

and p = 1- ((small^2)/(big^2))^1/f

That's the widths found.

what I want to do is move the x,y position on the image in the same proportion as the widths.

say x starts at 100 and ends at 800 I can apply the same equation to the x position and it sort of looks alright but I'm not sure it is tied properly to the widths.

I am struggling a bit working it out and wouldn't mind some help.

the first and last value of x is fixed and the frames (f) are fixed but somehow the change in x wants to be related to the formula to determine the width.

whatever the first change of x ( measured in pixels) x(1) to x(2) it will be a proportion of the first width ( measured in pixels) width(1) to width(2)

that proportion change of x wants to be of the same proportion as the next to last and last width.

I try to manipulate an image.

"zoom" in on it by cutting out a width from it.

each new image is proportionally smaller ( or bigger ) by the same amount

small=sqrt((big^2)*(1-p)^f)

where f is the next progression (frame) and p is the proportion

and p = 1- ((small^2)/(big^2))^1/f

That's the widths found.

what I want to do is move the x,y position on the image in the same proportion as the widths.

say x starts at 100 and ends at 800 I can apply the same equation to the x position and it sort of looks alright but I'm not sure it is tied properly to the widths.

I am struggling a bit working it out and wouldn't mind some help.

the first and last value of x is fixed and the frames (f) are fixed but somehow the change in x wants to be related to the formula to determine the width.

whatever the first change of x ( measured in pixels) x(1) to x(2) it will be a proportion of the first width ( measured in pixels) width(1) to width(2)

that proportion change of x wants to be of the same proportion as the next to last and last width.

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