Inserting Text on Image using Google Apps Script

This is a sample script for inserting a text on an image using Google Apps Script. The flow of this sample script is as follows:

1. Retrieve the image size using ImgApp.
2. Create new Google Slides with the custom page size using DocsServiceApp.
3. Put the image and text.
4. Export the result image

Source: Inserting Text on Image using Google Apps Script