@conference {spies2001c,
	title = {Surface expansion from range data sequences},
	booktitle = {Proceedings of the 23th DAGM Symposium on Pattern Recognition},
	year = {2001},
	pages = {163--169},
	publisher = {Springer},
	organization = {Springer},
	abstract = {We compute the range flow field, i.e. the 3D velocity field, of a moving deformable surface from a sequence of range data. This is done in a differential framework for which we derive a new constraint equation that can be evaluated directly on the sensor data grid. It is shown how 3D structure and intensity information can be used together in the estimation process. We then introduce a method to compute surface expansion rates from the now available velocity field. The accuracy of the proposed scheme is assessed on a synthetic data set. Finally we apply the algorithm to study 3D leaf motion and growth on a real range sequence.},
	doi = {10.1007/3-540-45404-7_22},
	author = {Hagen Spies and Bernd J{\"a}hne and John L. Barron}
}
@conference {jaehne1998b,
	title = {Study of dynamical processes with tensor-based spatiotemporal image processing techniques},
	booktitle = {ECCV 1998},
	volume = {1407},
	year = {1998},
	pages = {322--336},
	publisher = {Springer},
	organization = {Springer},
	abstract = {Image sequence processing techniques are used to study exchange, growth, and transport processes and to tackle key questions in environmental physics and biology. These applications require high accuracy for the estimation of the motion field since the most interesting parameters of the dynamical processes studied are contained in first-order derivatives of the motion field or in dynamical changes of the moving objects. Therefore the performance and optimization of low-level motion estimators is discussed. A tensor method tuned with carefully optimized derivative filters yields reliable and dense displacement vector fields (DVF) with an accuracy of up to a few hundredth pixels/frame for real-world images. The accuracy of the tensor method is verified with computer-generated sequences and a calibrated image sequence. With the improvements in accuracy the motion estimation is now rather limited by imperfections in the CCD sensors, especially the spatial nonuniformity in the responsivity. With a simple two-point calibration, these effects can efficiently be suppressed. The application of the techniques to the analysis of plant growth, to ocean surface microturbulence in IR image sequences, and to sediment transport is demonstrated.},
	doi = {10.1007/BFb0054750},
	author = {Bernd J{\"a}hne and Horst Hau{\ss}ecker and Hanno Scharr and Hagen Spies and Dominik Schmund and Ulrich Schurr}
}
