A way to your solution is to decouplate your images from their resolutions.
So you need to define the virtual size of each image.
You can define a class that will take filePath, virtualWidth, virtualHeight as arguments, as well as a draw method that take care of the scaling.
The virtual Width and Height are just the w/h of the images you have running right now.

That way when you load an image, whatever its resolution you'll be able to compute the scale to apply to it, and draw it with a correct size.
As a bonus you can even mix low-res/high res images depending on how important -or big- is the graphical object.

A way to your solution is to decouplate your images from their resolutions.
So you need to define the virtual size of each image.
You can define a class that will take filePath, virtualWidth, virtualHeight as arguments, as well as a draw method that take care of the scaling.
The virtual Width and Height are just the w/h of the images you have running right now.

That way when you load an image, whatever its resolution you'll be able to compute the scale to apply to it, and draw it with a correct size.
As a bonus you can even mix low-res/high res images depending on how important -or big- is the graphical object. (i did just that for a game i made and it worked fine).