Startup Idea: Engraving Instructions Application for Sign Shop

Startup idea to develop a software application tailored for integrating with a sign shop's cart system. The tool would be responsible for applying engraving instructions onto images for easier product visualization.

I am a web designer looking for a software application to apply engraving instructions to an image for a sign shop. I built a cart system for the customer but haven't been able to create or implement any type of software or programming application to accomplish this task.

The customer is more than willing to accept the finished project without the engraving application in the website but I'd still like to find a software application to complete the task for me before the site goes live. I've searched for engraving app, applying text to images and other general keywords. There are sites that do it but nothing out of the box that will accomplish the task.