Figure 4
Illustration of the motion estimation for the subsequent backprojection along curved paths. Two successive reconstructions (a) are analyzed by an optical flow algorithm. The depicted result shows the shrinking at the borders of the match. The color indicates the direction of motion as shown by the color wheel, the saturation gives the motion amplitude with a maximum of 12 px for all images shown. The image series in (b) gives an overview of the dynamics of the entire burning process, showing the optical flow result for every third frame. Using the motion information, the reconstruction is the carried out by backprojection on dynamically curved paths, as illustrated in (c) with a magnification of the motion amplitude by the factor of 3 for better visibility. A significantly improved reconstruction quality is observed, see the fine object details resolved in (e), compared to the result of (d) a conventional direct FBP reconstruction.
