Fairly straightforward with Cloudinary.
The general form is:
https://res.cloudinary.com/<YOUR_CLOUDINARY_ID>/image/upload/l_<IMAGE 1>,[TRANSFORMATION OPTIONS]/<IMAGE 2>
Some examples of a couple that I did just last night…
In the screenshots shown there, the two lower images shown in each are a composite of two images, with some text overlay. So:
- Base image
- Second image overlay
- Text overlay