Camera-Proxy Enhanced Identity-Recalibration Learning for Unsupervised Visible-Infrared Person Re-Identification

Visible-Infrared person Re-Identification (VI-ReID) involves querying images of the same person across visible and infrared modalities. To minimize annotation costs, Unsupervised Visible-Infrared person Re-Identification (UVI-ReID) using pseudo-label contrastive learning has emerged. Traditional UVI-ReID approaches often neglected camera domain information and relied on inadequate update strategies during training, only using cosine distance for testing, which led to incorrect mapping of cross-modal relationships. To address these issues, we propose Camera-proxy Enhanced Identity-recalibration Learning (CEIL). It consists of two main stages: first, it employs intra-modal contrastive learning in conjunction with the camera-proxy, updates the memory bank using our innovative Difficulty-aware Cluster-based Memory Updating (DCMU) strategy, and applies Camera Domain-driven Local correlation (CDL) Loss to enhance the learning process. Then utilizes cross-modal contrastive learning, featuring our Proxy-enhanced Cross-modal Mapping (PCM) module, to recalibrate the identity relationships between different modalities. Graph network-based Camera constraint adjustment Re-ranking (GCR) method is adopted during test, utilizing camera domain information to recalibrate the correspondence between identities. Extensive experiments have demonstrated that CEIL achieving state-of-the-art performance on the SYSU-MM01, RegDB, and LLCM datasets and the GCR, as a general unsupervised re-ranking method, can further enhance performance of model on these datasets. The code will be released at <uri xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">https://github.com/maybeextra/CEIL</uri>.