Perform coordinate transformations on partitioned images to match feature points of two images

Hi, I need to code image morphing in matlab.As a part of the algorithm I need to perform coordinate transformations on the partitioned images to match the feature points of these two images. The coordinate transformations are affine transformation or bilinear transformation.

Example of two images:

image1: http://www.crocko.com/92A5F93912BD411C81D5DAFD26492575/ally.jpg

image2: http://www.crocko.com/EF180CF97EE3449CA8829AF82BC2AD71/lion.jpg

Output after transformation:

image1 transformed: http://www.crocko. com/407346490C1749BF97F1AC60584C8732/warped_ally.jpg

image2 transformed: http://www.crocko.com/38CF6AE816E44DAF885AD208F5F29D59/warped_lion.jpg

Equations for the coordinates transformation: http://www.crocko.com/B7A01EC313684CEBB00CD416EF9FD0CA/affine_eq.jpg http://www.crocko.com/1859259A957A4C71A0C58CD0C0079164/bilinear_eq.jpg

The question is how to code the transform in matlab? Does anybody can share an idea or similar made code to perform the necessary coordinates transformation on two images in loop and to get the results above?

Answer 1

[Image Analyst]

I can't see your images, just some ad for a web hosting service. Try tinypic.com instead.

[Pavl M.]

The images to this question reuploaded to tinypic.com are:

a.Affine transformation:

[IMG]http://i44.tinypic.com/be7gbc.jpg[/IMG]

b.Bilinear transformation:

[IMG]http://i40.tinypic.com/2im5821.jpg[/IMG]

c.Mesh(quadrangels,triangles) general transformation:

[IMG]http://i41.tinypic.com/2yvuryq.gif[/IMG]

d.Input image 1:

[IMG]http://i39.tinypic.com/dc3fw2.png[/IMG]

e.Input image 2:

[IMG]http://i39.tinypic.com/34fe2qx.png[/IMG]

f.Output( after transformation ) image 1:

[IMG]http://i41.tinypic.com/25s8mmr.png[/IMG]

g.Output ( after transformation ) image 2:

[IMG]http://i40.tinypic.com/28v7nc.png[/IMG]

The question is code for both transforms in matlab ( in loop for 2D input images ).

Thank you.

[Image Analyst]

Try imtransform().

[Pavl M.]

imtransform(...) suits the needs. Is there any open source matlab code for image morphin that can produce the images above ?

Thank you.

[Image Analyst]

I don't know. You'd probably have to write your own code that took input control points and then output (destination) points for them, then call imtransform. You could use ginput() to ask the user to click the points that you want to move.