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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Comparison of Sparse To Dense with Dense To Sparse
Step1:  First we read our images. This one is a sparse image
Step2:  This image is a dense image
Step3:  Here's the difference between the 2 images before registration
Step4:  Sparse to Dense Registration
Now we register the sparse image to the dense image
Step5:  We evaluate the registration using the difference between the deformed sparse image and dense image
Step6:  Dense to sparse Registration
Next we register the dense image to the sparse image
Step7:  We evaluate the registration using the difference between the sparse image and deformed dense image
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Python Code:
from ndreg import *
Explanation: Comparison of Sparse To Dense with Dense To Sparse
End of explanation
sparseImg = sitk.Cast(imgRead("../dat/sparse/sparse.img"), sitk.sitkFloat32)
imgShow(sparseImg)
Explanation: First we read our images. This one is a sparse image
End of explanation
denseImg = sitk.Cast(imgRead("../dat/sparse/dense.img"), sitk.sitkFloat32)
imgShow(denseImg)
Explanation: This image is a dense image
End of explanation
imgShow(sparseImg - denseImg, cmap=plt.cm.jet)
Explanation: Here's the difference between the 2 images before registration
End of explanation
alpha=0.1
epsilon = None
(field, invField) = imgMetamorphosis(sparseImg, denseImg, alpha=alpha, epsilon=epsilon, verbose=True)
outSparseImg = imgApplyField(sparseImg, field)
imgShow(outSparseImg)
Explanation: Sparse to Dense Registration
Now we register the sparse image to the dense image
End of explanation
imgShow(outSparseImg - denseImg, cmap=plt.cm.jet)
Explanation: We evaluate the registration using the difference between the deformed sparse image and dense image
End of explanation
(field, invField) = imgMetamorphosis(denseImg, sparseImg, alpha=alpha, verbose=True)
outDenseImg = imgApplyField(denseImg, field)
imgShow(outDenseImg)
Explanation: Dense to sparse Registration
Next we register the dense image to the sparse image
End of explanation
imgShow(sparseImg - outDenseImg, cmap=plt.cm.jet)
Explanation: We evaluate the registration using the difference between the sparse image and deformed dense image
End of explanation
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