This software uses the affine transformation to register images. These are the kind of images obtained by a
distant camera viewing a rather flat scene from an angle. The registration is automatic. The user only
provides the names of the two image files to be registered. The program will then register the images and
display the result. The program selects a set of landmarks in each image, determines the correspondence
between the landmarks, and determines the transformation parameters from the correspondences.
Assumptions: It is assumed that
If one or more of these assumptions are violated, the program may register the images approximately, or
report a failure.
Modes of operation: The program operates at three different modes.
distant camera viewing a rather flat scene from an angle. The registration is automatic. The user only
provides the names of the two image files to be registered. The program will then register the images and
display the result. The program selects a set of landmarks in each image, determines the correspondence
between the landmarks, and determines the transformation parameters from the correspondences.
Assumptions: It is assumed that
- parallel lines in the scene remain parallel in the images
- the images are in the same modality,
- at least 50% overlap exists between the images.
If one or more of these assumptions are violated, the program may register the images approximately, or
report a failure.
Modes of operation: The program operates at three different modes.
- Default mode: This is a fast initial mode used to register the images quickly. For some images, this is
sufficient. - Redo mode: For images with considerable intensity differences, it may be necessary to redo the
registration using a larger number of landmarks. The user presses a Redo button after viewing the
registration result of the default mode. - Refinement mode: In this mode, the positions of the landmarks are more accurately determined by
template matching and the registration is repeated. Examples of image registration by this software are
given below.
(a)
(b)
(c)
(d)
Fig. 1. (a), (b) Two images of a quilt on a wall from slightly different views. (c) Registration using the default
mode. This takes about half a minute. (d) Refinement of the registration. This takes a few seconds. Some
misregistration can be observed in the lower right part of the image. This is the best affine transformation can do
for these images, which represent different views of a flat scene. A better transformation function for registration
of such images is projective. For the registration result using the projective transformation see the Auto.
Projective Registration page. Affine transformation is more suitable for registration of satellite images as shown
below.
mode. This takes about half a minute. (d) Refinement of the registration. This takes a few seconds. Some
misregistration can be observed in the lower right part of the image. This is the best affine transformation can do
for these images, which represent different views of a flat scene. A better transformation function for registration
of such images is projective. For the registration result using the projective transformation see the Auto.
Projective Registration page. Affine transformation is more suitable for registration of satellite images as shown
below.
(a) (b)
(c) (d)
Fig. 2. (a), (b) Two Landsat images with small view-angle differences. (c) Initial registration. (d) Refined
registration using the affine transformation.
registration using the affine transformation.
To obtain a license for this registration software, place an order here =>
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| 2-D auto affine registration |
| Image Fusion Systems Research |