CamlImages is an image processing library, which provides

* Basic functions for image processing and loading/saving various image
  file formats (hence providing a translation facility from format to
  format),
* An interface with the Caml graphics library allows to display
  images in the Graphics module screen and to mix them with Caml
  drawings,
* A freetype interface, integrated into the library:
  you can draw texts into images using any truetype fonts.

In addition, the library can handle huge images that cannot be (or can
hardly be) stored into the main memory (the library then automatically
creates swap files and escapes them to reduce the memory usage).