Swap selected images
This tool reverts an optimised image back to its original version.
If you need to revert an optimised image(s) to the original version, first select in the document with InDesign’s Selection Tool (V) and then choose click Swap selected images.
The scaling and placement of the image is retained. You can check the Links panel to verify that the images have been swapped.
In InDesign you can elect to view an additional column in the Links panel to check the Effective PPI of images within the document:
To add the column choose InDesign Window menu > Links > Panel Options from the panel menu: