4. A patient undergoes serial MRI scans at different time po…
4. A patient undergoes serial MRI scans at different time points to track the progression of a brain tumor. Due to slight variations in patient positioning, image registration is required to align the scans properly before analysis. 4.1 If the image is rotated by 30 degrees after the treatment, will all pixels still align perfectly with the original grid coordinates? (If yes, explain why. If no, explain why not.) If not, how do we determine the intensity values for the new off-grid pixel coordinates? (Answer this question using the method name) 4.2 As we know, image interpolation is necessary for some image registration tasks. Demonstrate how to calculate the pixel value using bilinear interpolation for a given yellow pixel in Figure 5(B). 4.3 We know that the following equation (Eq.1) is useful for affine transformation of an image. Given that a point in an image with coordinates (2,0) is found at the new coordinate (0,2) after an affine transformation, please provide one possible solution of possible transformation matrices under the assumption that e=0 and f=0. 4.4 You still have one point at (5, 2). Use your transformation matrix calculated in 4.3, assuming that e=2, and f=3, what will be the new coordinate of (5,2) after your transformation?