How to prevent seeing image from browser but allow on desktop app

I'm developing a desktop app connected to a website. I store the user profile images in the file system of a web server so I can reach them from the URL, the problem is that I don't want that someone can access the images from any web browser like chrome.

Is there a way in which I can access the images through the URL and display them in my desktop app (built with qt) but also prevent accessing these images from a regular web browser.

The desktop app user is incapable of seeing the URL from the image tough.