A Hashing Application:
Finding Geometric Patterns

A Pattern Matching Example

Finding Geometric Patterns Efficiently

A Simple Pattern Matching Algorithm

How do we detect a hit?

An Improved Pattern Matching Algorithm

Is it better?

Why check every pattern point?

Improvement Using Hashing

What if we have to handle both translation and rotation?

Geometric Hashing

Geometric Hashing, Continued

Geometric Hashing Advantages

Usage of Geometric Hashing