Points Registration

Registration

The registration is started by Registration > Register in the Registration by reference points dialog.

Then choose registration method in the Iterative registration dialog – pairwise or iterative:

Pairwise Registration

Used in most cases.

For the pairwise registration, two groups of points should have minimum three reference points with the same names.

For example, there are two groups: А and B.

Each group has 4 reference points.

Group A contains reference points with the names 1, 2, 3, 4, group B – 1, 2, 3, 5.

Pairwise registration is available in this case – groups A and B contain three points with coinciding names – points 1, 2 and 3.

Another example, when we have three groups: А, B and C.

Each group has 4 reference points.

Group A contains reference points with the names 1, 2, 3, 4, group B – 1, 2, 3, 5, group C – 1, 4, 5, 6.

The pair A and С, as well as the pair B and C, do not have three coinciding points.

But if first register the pair A and B (they have coinciding points 1, 2 and 3), and then merge them to AB group with points 1, 2, 3, 4, 5, afterwards we can register pairs AB and С, since they will have common points 1, 4 and 5.

Group Set

If all of groups cannot be registered pairwise, the dialog offers to select one of available group sets:

Select set of groups. Other groups will be removed from registration and marked as Disabled.

Iterative Registration

Iterative registration is used when pairwise registration is not available. This registration makes a consistent approach to the specified accuracy.

For example, there are three groups: А, B, C.

Each group has 3 reference points.

Group A contains reference points with names 1, 2, 3, group B – 1, 2, 4, group C – 1, 3, 4.

Pairwise registration requires minimum three referenced points with the same names. In this case any pair of groups has only two appropriate points (for groups A and B they are points 1 and 2, for A and C – 1 and 3, for B and C – 1 and 4).

Nevertheless, correct registration is available in this case with help of iterative registration.

After choosing the iterative registration method, the following dialog is displayed:

Options: