Two Algorithms

Two algorithms provide processing flexibility.

ADJUST offers two complimentary processing algorithms, Best Fitting and Rubber Sheeting.

Best Fitting is a linear process, performing Move, Scale and Rotate operations to all elements as a group (this insures that angle relationships remain unchanged). Best Fitting is a good pre-process for Rubber Sheeting but can be used alone (Scaling and/or Rotation can be disabled for flexibility). Our best fit algorithm is similar to a Helmert transform and some of our surveyor customers use this process in place of Least Squares in some applications. Our best fit algorithm finds a solution with the lowest maximum error rather than the lowest average error and it works in 2D or 3D.

Rubber Sheeting uses a unique non-projective, non-TIN based algorithm to guarantee a Zero error at every calibration point. Our algorithm is unique among rubber sheeting methods, allowing Unlimited Calibration, meaning you can define any number of calibration coordinate pairs (FROM point & TO point) which can be arranged in any pattern, even so called unstable or conflicting patterns.

Other rubber sheeting methods which use projective or TIN based algorithms require careful selection of calibration pairs. Those methods frequently fail or produce unacceptable results if too many calibration pairs or conflicting (unstable) patterns are used. (see Solution: Rubber Sheeting in “corridor” applications – Unstable Calibration )

Since ADJUST uses a unique non-projective algorithm you are free to define any rubber sheeting pattern that suits the task. The ability to use any number of calibration points and the guarantee of zero error makes ADJUST very useful for Precision Mapping applications.