lsqnonlin and rotation problem

Hello,

i'm sorry for this basic question but i have some problems with lsqnonlin and image registration. I want to use lsqnonlin in order to find the rotation (just the rotation because it's a study case) whish has been applied to a reference image. I use direct registration method comparing the intensity of the two images (reference and rotated image).

basically the pseudo code looks like that:

% load reference image % apply a rotation to the reference image im2 = imrotate(imref,23,'bicubic','crop');

% roiCmp is the subarea of the reference image which is considered for comparing intensity beetween ref and im2 guessValue = [10]; [afrotation,resNorm,residual,exitFlag] = lsqnonlin(@fitRot, guessValue, [], [], options,imref,im2, roiCmp);

%% The function fitRot use imrotate to rotate im2: function err = fitRot(x0,ref,tar,roiCmp)

rTrg = imrotate(sTrg,x0(3),'bicubic','crop');
overallRes = abs(double(rTrg) - double(ref));

resTemp = abs(overallRes(roiComp(2):roiComp(2)+roiComp(4),roiComp(1):roiComp(1)+roiComp(3)));
res = resTemp(:);

end

When i run this algorithm, it obtain the same result as my initial guess. I have no warning or error message and their is 3 step of optimisations but no change ...

Any help will be appreciate. Thx all (i hope to be clear and again sorry for this basic question)

[AD]

I have almost exactly the same problem