How to create dynamic Image based on content external path+file

I have a PDF document with one first page where I want to put an image based on the path + filename of the external image-file (JPG).

If I change the picture (keeping path and filename), I want that the image on this (PDF) first page, automatically show the right image/picture

Target:
I have two photos (one file with a blue car "bluecar.jpg" and another file with a red car "redcar.jpg") On that PDF first-page, I want to display the content of my JPG-File: c:\temp\car.jpg

Scenario / desired solution:
If I save the image of the "blue car" with the filename: c:\temp\car.jpg ... in the PDF document should be the "blue car"

If I save the image of the "red car" in the same path with the same filename: c:\temp\car.jpg ... in the PDF document should be displayed the "red car" image

How can I show images in a PDF document based on the real file content? ... like fields displaying data based on the external .FDF file?

I try to put an image and test if I change the original file, that image would change... but it keeps still the same image, that I used at the first time.

No image automatically refreshes will happen...