3 research outputs found
Frugal Satellite Image Change Detection with Deep-Net Inversion
Change detection in satellite imagery seeks to find occurrences of targeted
changes in a given scene taken at different instants. This task has several
applications ranging from land-cover mapping, to anthropogenic activity
monitory as well as climate change and natural hazard damage assessment.
However, change detection is highly challenging due to the acquisition
conditions and also to the subjectivity of changes. In this paper, we devise a
novel algorithm for change detection based on active learning. The proposed
method is based on a question and answer model that probes an oracle (user)
about the relevance of changes only on a small set of critical images (referred
to as virtual exemplars), and according to oracle's responses updates deep
neural network (DNN) classifiers. The main contribution resides in a novel
adversarial model that allows learning the most representative, diverse and
uncertain virtual exemplars (as inverted preimages of the trained DNNs) that
challenge (the most) the trained DNNs, and this leads to a better re-estimate
of these networks in the subsequent iterations of active learning. Experiments
show the out-performance of our proposed deep-net inversion against the related
work.Comment: arXiv admin note: text overlap with arXiv:2212.1397
Adversarial Virtual Exemplar Learning for Label-Frugal Satellite Image Change Detection
Satellite image change detection aims at finding occurrences of targeted
changes in a given scene taken at different instants. This task is highly
challenging due to the acquisition conditions and also to the subjectivity of
changes. In this paper, we investigate satellite image change detection using
active learning. Our method is interactive and relies on a question and answer
model which asks the oracle (user) questions about the most informative display
(dubbed as virtual exemplars), and according to the user's responses, updates
change detections. The main contribution of our method consists in a novel
adversarial model that allows frugally probing the oracle with only the most
representative, diverse and uncertain virtual exemplars. The latter are learned
to challenge the most the trained change decision criteria which ultimately
leads to a better re-estimate of these criteria in the following iterations of
active learning. Conducted experiments show the out-performance of our proposed
adversarial display model against other display strategies as well as the
related work.Comment: arXiv admin note: substantial text overlap with arXiv:2203.1155
Frugal Reinforcement-based Active Learning
Most of the existing learning models, particularly deep neural networks, are
reliant on large datasets whose hand-labeling is expensive and time demanding.
A current trend is to make the learning of these models frugal and less
dependent on large collections of labeled data. Among the existing solutions,
deep active learning is currently witnessing a major interest and its purpose
is to train deep networks using as few labeled samples as possible. However,
the success of active learning is highly dependent on how critical are these
samples when training models. In this paper, we devise a novel active learning
approach for label-efficient training. The proposed method is iterative and
aims at minimizing a constrained objective function that mixes diversity,
representativity and uncertainty criteria. The proposed approach is
probabilistic and unifies all these criteria in a single objective function
whose solution models the probability of relevance of samples (i.e., how
critical) when learning a decision function. We also introduce a novel
weighting mechanism based on reinforcement learning, which adaptively balances
these criteria at each training iteration, using a particular stateless
Q-learning model. Extensive experiments conducted on staple image
classification data, including Object-DOTA, show the effectiveness of our
proposed model w.r.t. several baselines including random, uncertainty and flat
as well as other work.Comment: arXiv admin note: text overlap with arXiv:2203.1156