how to write matlab code for a rotation invariant of a point(x,y)

i am doing matching algorithm for fingerprint. in this matching input fingerprint is rotated so the point also got rotated . how to match the rotated point with normal point because i need to calculate the distance. while calculating if the distance is same its a same point due to rotation distance vary..

Answer 1

[danny]

have a look at the procrustes function

[d,Z,tr] = procrustes(X, Y);

it takes two sets of points; the original points(X) and the rotated/translated points(Y),

it will give you both the translation and rotation inside tr.

[Thangameena]

if i use this code. when i display tr i will get T=[74x104 double]; b=0; c=[1x104 double]. i dint understood what it is. i will explain that i have a set of 60 (x,y) points as a template(stored).. i will get one template(input) with set of approximately 30 to 60 (x,y)points.. but these input points may be rotated or translated.. i have to calculate the distance between two points (both in stored and input template). if the two distance(calculated input template and stored template) is equal those two are same point.. my problem is the input point is slightly translated so the (x,y)values will vary in input. because of this variation my distance is also vary.. so how can i found which point is translated/rotated. then i need to rotate as a original template. after that i will do matching