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Regular Pyramids

There are two terms to describe the structure of a regular pyramid:

  1. the reduction factor, which determines the rate by which the number of cells decrease from level to level, and
  2. the reduction window, which associates a set of cells of the level directly below to every (higher level) cell. It covers the area of its associated cell. Reduction windows are mostly rectangular shaped.
Formally, the structure of a regular pyramid will be described by (number of colums) x (number of rows) / (reduction factor).
A pyramid is defined by its structure and its operation, which is responsible for the bottom-up information flow within the pyramid. This operation is called the reduction function.

In gray level pyramids, the contents of cells are gray values or color vectors. Every level of the pyramid is a picture. Different reduction functions can be used to fill the bottom-up cells of the pyramid.

regular.gif Examples