(09-08-2025, 12:43 PM)TMORT Wrote: I don't want to georeference all those points on this new image. It seems like there should be a relationship between the x, y coordinates of the pixels of the two images so I should be able to calculate where a pixel from the old image will line up on the new image.
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I have read that the scaling tool has a number of interpolation methods and that may influence this relationship.
Gimp might not be accurate enough for your needs however, first a general comment.
The aspect ratio (height/width) for each is not identical big = 2.70148 small = 2.6988 A very small difference that might make only 5 pixels out over 10,000 pix but up to you to decide. Scaling in mm units might make that difference, work in pixels.
Edit: This is what I mean. The width should be 3776 pix not 3772 only 4 pix but.....
The interpolation method should make no difference in image pixel size, it only affects quality, although a single pixel in the small image might spread out a bit when upscaled.
Pleased that you are working in pixels.
and I hope still using Gimp 2.10Ofnuts has a Gimp 2.10 plugin ofn-path-edits.py from http://sourceforge.net/projects/gimp-pat...s/scripts/ that gives pixel co-ordinates , start and end of a path(s) It might allow you to calculate relative positions. (but remember that difference in aspect ratios)