  Person re-identification (Re-ID) aims at recognizing the same person from
images taken across different cameras. To address this task, one typically
requires a large amount labeled data for training an effective Re-ID model,
which might not be practical for real-world applications. To alleviate this
limitation, we choose to exploit a sufficient amount of pre-existing labeled
data from a different (auxiliary) dataset. By jointly considering such an
auxiliary dataset and the dataset of interest (but without label information),
our proposed adaptation and re-identification network (ARN) performs
unsupervised domain adaptation, which leverages information across datasets and
derives domain-invariant features for Re-ID purposes. In our experiments, we
verify that our network performs favorably against state-of-the-art
unsupervised Re-ID approaches, and even outperforms a number of baseline Re-ID
methods which require fully supervised data for training.
