Traditionally, scientific fields have defined boundaries, and scientists
work on research problems within those boundaries. However, from time to
time those boundaries get shifted or blurred to evolve new fields. For
instance, the original goal of computer vision was to understand a
single image of a scene, by identifying objects, their structure, and
spatial arrangements. This has been referred to as image understanding.
Recently, computer vision has gradually been making the transition away
from understanding single images to analyzing image sequences, or video
Video understanding deals with understanding of video understanding.
sequences, e.g., recognition of gestures, activities, facial
expressions, etc. The main shift in the classic paradigm has been from
the recognition of static objects in the scene to motion-based
recognition of actions and events. Video understanding has overlapping
research problems with other fields, therefore blurring the fixed
boundaries. Computer graphics, image processing, and video databases
have obvi- ous overlap with computer vision. The main goal of computer
graphics is to generate and animate realistic looking images, and
videos. Re- searchers in computer graphics are increasingly employing
techniques from computer vision to generate the synthetic imagery. A
good exam- pIe of this is image-based rendering and modeling techniques,
in which geometry, appearance, and lighting is derived from real images
using computer vision techniques. Here the shift is from synthesis to
analy- sis followed by synthesis. Image processing has always overlapped
with computer vision because they both inherently work directly with
images.