Difference between two revisions of the same record

Hi,
I've a small task that I don't manage to do: find the difference between two revisions of the same record. 

I've different status for the same records. 
The typical path is: 

•     Creation of the records – Status is set to  "created" and version to 1
•     When the user is done a button allow the status to change to "validated" – with the security parameter this version is not editable any more
•     When a revision is needed I've another button that duplicate the record and set the revision to 2 and change the status to "under revision"
•     Again when the user is done a button allow the status to change to "validated" 
•     … for as many revision as it takes

I'd like to find a simple method to know the changes made between two validated versions.
I thought of comparing the two records and return the fields (with the values) that have changed. Does anyone have a solution? Is there a better way?

I don't want a full audit trail as I only need the changes made between the two validated records.

Thanks for your help