Dialog in painting, 1333: words in an air - Simone Martini \"The Angel and the Annanciation\",
Click the picture to see annotations
Dialog in painting: Simone Martini The Angel and the Annanciation, 1333 - detail
What is image annotation?
One can see text going from the Angel toward Virgin Mary written just over painting. Later this 'functionality' will be implemented by scroll, and in comics with balloons.
See next post for example of scrolls to represent dialog in painting in 15 century