Learning Cross-View Geo-Localization Embeddings via Dynamic Weighted Decorrelation Regularization

In the domain of cross-view geo-localization, the challenge lies in accurately matching images captured from distinct perspectives, such as aerial drone imagery and satellite imagery of the same geographical location. Existing methods predominantly concentrate on minimizing distances between feature embeddings in the representational space, inadvertently overlooking the significance of reducing embedding redundancy. This oversight potentially hampers the extraction of diverse and distinctive visual patterns critical for precise localization. This work argues that minimizing embedding redundancy is a pivotal factor in enhancing a model's ability to discriminate diverse scene characteristics. To support this claim, we introduce a straightforward yet effective regularization technique, termed dynamic weighted decorrelation regularization (DWDR). DWDR serves to actively promote the learning of orthogonal feature channels within neural networks. By dynamically adjusting weights, DWDR targets the minimization of interchannel correlations, guiding the correlation matrix toward diagonality, indicative of independence among channels. The dynamic weighting mechanism adaptively prioritizes the decorrelation of channels that remain highly correlated throughout training. Additionally, we devise a symmetrical sampling strategy for cross-view scenarios to ensure that the training examples are balanced across different imaging platforms in a batch. Despite its simplicity, the integration of DWDR and the proposed sampling scheme yields remarkable performance across four extensive benchmark datasets: University-1652, CVUSA, CVACT, and VIGOR. Notably, in stringent conditions, such as when constrained to exceedingly compact feature dimensions of 64, our methodology significantly outperforms conventional baselines, thereby affirming its efficacy and robustness under challenging constraints.