  Recent machine learning strategies for segmentation tasks have shown great
ability when trained on large pixel-wise annotated image datasets. It remains a
major challenge however to aggregate such datasets, as the time and monetary
cost associated with collecting extensive annotations is extremely high. This
is particularly the case for generating precise pixel-wise annotations in video
and volumetric image data. To this end, this work presents a novel framework to
produce pixel-wise segmentations using minimal supervision. Our method relies
on 2D point supervision, whereby a single 2D location within an object of
interest is provided on each image of the data. Our method then estimates the
object appearance in a semi-supervised fashion by learning
object-image-specific features and by using these in a semi-supervised learning
framework. Our object model is then used in a graph-based optimization problem
that takes into account all provided locations and the image data in order to
infer the complete pixel-wise segmentation. In practice, we solve this
optimally as a tracking problem using a K-shortest path approach. Both the
object model and segmentation are then refined iteratively to further improve
the final segmentation. We show that by collecting 2D locations using a gaze
tracker, our approach can provide state-of-the-art segmentations on a range of
objects and image modalities (video and 3D volumes), and that these can then be
used to train supervised machine learning classifiers.
