How to rename the person image downloaded using rtf template in BI Publisher

Summary:

Requirement to download the person image (person photo) from Oracle cloud HCM. I am able to download it but not sure how to rename the default name of the photo with the person number.

Content (required):

I have a requirement to download photos of all employees from Cloud HCM application with the photo name as person number for unique identification for the photo. I am able to download the photos in jpg format using rtf template (attached here) and able to download the photo from report output. All photos are downloaded with the name which is not meaningful to identify the uniqueness.