In most domain adaptation methods, concurrent access to source and target data isneeded. In many real-life problem statements, it’s highly likely that the access to the source
data might not be possible during the adaptation process. Source-free domain adaptation
methods, while very necessary, usually have significant performance gap when compared
with those that assume access to the source data. To tackle this, we introduce a source
free domain adaptation strategy for the semantic segmentation problem that internally uses
active learning on the pixel level predictions (i.e., pseudo labels) to obtain a framework that
can generalize well between the source and the target domain. Given a small budget for
labeling, we select the pixels needed to be sent to an oracle for labeling. These labeled
pixels are then used to boost performance of the the overall system. Our method does not
assume any source data or any prior labels available on the target data. We observe that
even without the source data and only by labeling a small percentage of pixels using active
learning, we can still reach comparable performance with many standard unsupervised
domain adaptive semantic segmentation methods.We also show a brief example application
of domain adaptation on the environmental scenario