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lock042

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Hello everybody,

Sorry to ask you something that may be easy for you but I'm stuck.

For example I have 2 images (size 2056x2056). One image of reference and the other is the same rotated from -90degrees.

Using a program with keypoints, it gives me a transform matrix :

a=2.056884522e+03 b=1.153333964e-04 c=-9.999797329e-01

d=1.767228039e-01 e=9.998105577e-01 f=4.144966751e-06.

Now I try to recover the transform parameters : translation, rotation and scale.

For rotation I have :

θ = atan2(c, b) = -89.99

For scale :

scale = sqrt(b * b + c * c) = 1.0

But for translation I'm stuck.

In a system transformation where rotation is negligeable, it's easy because a and d describe the translation between the two systems with dx = a and dy = -d but here, it is not negligeable and I should find

dx = 0.0

dy = 0.0

Could you help me ?lock

Sorry to ask you something that may be easy for you but I'm stuck.

For example I have 2 images (size 2056x2056). One image of reference and the other is the same rotated from -90degrees.

Using a program with keypoints, it gives me a transform matrix :

a=2.056884522e+03 b=1.153333964e-04 c=-9.999797329e-01

d=1.767228039e-01 e=9.998105577e-01 f=4.144966751e-06.

Now I try to recover the transform parameters : translation, rotation and scale.

For rotation I have :

θ = atan2(c, b) = -89.99

For scale :

scale = sqrt(b * b + c * c) = 1.0

But for translation I'm stuck.

In a system transformation where rotation is negligeable, it's easy because a and d describe the translation between the two systems with dx = a and dy = -d but here, it is not negligeable and I should find

dx = 0.0

dy = 0.0

Could you help me ?lock

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