  Advancement of imaging techniques enables consecutive image sequences to be
acquired for quality monitoring of manufacturing production lines. Registration
for these image sequences is essential for in-line pattern inspection and
metrology, e.g., in the printing process of flexible electronics. However,
conventional image registration algorithms cannot produce accurate results when
the images contain many similar and deformable patterns in the manufacturing
process. Such a failure originates from a fact that the conventional algorithms
only use the spatial and pixel intensity information for registration.
Considering the nature of temporal continuity and consecution of the product
images, in this paper, we propose a closed-loop feedback registration algorithm
for matching and stitching the deformable printed patterns on a moving flexible
substrate. The algorithm leverages the temporal and spatial relationships of
the consecutive images and the continuity of the image sequence for fast,
accurate, and robust point matching. Our experimental results show that our
algorithm can find more matching point pairs with a lower root mean squared
error (RMSE) compared to other state-of-the-art algorithms while offering
significant improvements to running time.
