Step 6: Using XData and YData Output Values :: Spatial Transformations (Image Processing Toolbox User's Guide)

Image Processing Toolbox User's Guide

Step 6: Using XData and YData Output Values

Another approach is to compute the full extent of the registered image and use the optional imtransform syntax that returns the x- and y-coordinates that indicate the transformed image's position relative to the base image's pixel coordinates.

[registered2 xdata ydata] = imtransform(unregistered, tform,...
                                        'FillValues', 255);

Display the registered image. Overlay a semi-transparent version of the base image for comparison. Adjust the axes to include the full base image. In this case, notice how the registration is evident and the full extent of both images is visible as well.

figure; imshow(registered2, 'XData', xdata, 'YData', ydata)
hold on
h = imshow(base, gray(256));
set(h, 'AlphaData', 0.6)
ylim = get(gca, 'YLim');
set(gca, 'YLim', [0.5 ylim(2)])

Step 5: Using XData and YData Input Parameters Image Registration