Babl is a dynamic, any to any, pixel format conversion library. It provides conversions between the myriad of buffer types images can be stored in. Babl doesn't only help with existing pixel formats, but also facilitates creation of new and uncommon ones.
vector-based drawing program, like CorelDraw® or Adobe Illustrator® from the proprietary software world, and Sketch or Karbon14 from the free software world.