What is matte lines?

Matte lines are the boundaries between the original footage and the added elements in special effects work. They are created by using a matte, or a mask, which allows the effect to appear behind the foreground image. Matte lines are crucial to ensure that the added elements look like they are part of the scene, and not just floating on top of it. They must be carefully crafted to blend seamlessly with the original elements. Matte lines used to be drawn by hand, but now they are created digitally using software like Adobe After Effects or Autodesk Flame. The key to creating good matte lines is attention to detail and careful planning and execution.