How to rotate some part of image?

I have dataset of finger images; but some fingers are not captured in straight way; and they are misalighned at some other angle due to which I cannot get mask of that image properly. Now I want to rotate all those fingers only so that background can be removed easily with well alighned fingers. Following is misalighned finger image.

I need images with straight fingers.

How I can do it?

[Matt J]

How is the orientation of the finger measured?

How are you getting the mask when the finger is aligned the way you'd like it?

[Imran Riaz]

This is the masked image in above figure. I also want to remove the black area. But when i apply loop to select the only 1's values and ignore the zeros. The image is cut down from right side and from left side some black portion at bottom side is also present.

So if the fingure is in straight position it can be easily removed.

Answer 1

[Narvik]

Hi,

I understand that you want to rotate images so that they are aligned in specific manner.

This can be done by applying geometric transformation on the image using the “imwarp” function. For more information, refer to the following documentation:

https://www.mathworks.com/help/images/ref/imwarp.html

You can also use the “Registration Estimator” app to align the misaligned images. Please refer to the documentation of “Registration Estimator” app below:

https://www.mathworks.com/help/images/ref/registrationestimator-app.html

Hope this helps!

Answer 2

[Image Analyst]

You can use the radon transform to determine the angle you need to rotate by. See how I rotated the football in the attached demo.

Answer 3

[DGM]

This question is one in a long set of unclear questions which together likely form an XY problem.

This is a rough summary of a large portion of the set of given questions, with some examples.

https://www.mathworks.com/matlabcentral/answers/1773635-image-remapping-using-pixel-values#answer_1305916

[Image Analyst]

Yes, he just says "I need images with straight fingers." without any justification for why. I'd like to know the reason why. I'd bet it is not really needed, and if we knew the steps he was going to take after it was rotated, we could determine if rotation was really needed.

https://en.wikipedia.org/wiki/XY_problem