Why Do We need to be Able to See Motion?

How do we use visual motion information

• To see where animals are going,
  • so you can avoid them if they're coming after you
  • or so you can catch tehm if you're going after them.
• Lip reading
• Detecting face expression

Might this ability be important enough that our brains would allocate special machinery to seeing motion?

If you had to write an algorithm to take video input and figure out if an object is moving or in what direction, what would that code look like?

David Marr

• We cannot understand perception without thinking about
  • what each perceptual inference is necessary for ecologically,
  • the computational challenges involved in making that inference.