Multi-scale representations are motivated by the scale invariant properties of natural images. While many low level statistical measures, such as the local mean and variance of intensity, behave in a scale invariant manner, there are many higher order deviations from scale invariance where zero-crossings merge and disappear. Such scale variant behavior is important information to represent because it is not easily predicted from lower resolution data. A scale variant image pyramid is a representation that separates this information from the more redundant and predictable scale invariant information.