Improving Zero-Shot Object-Level Change Detection by Incorporating Visual Correspondence

Detecting object-level changes between two images across possibly different views (Fig. 1) is a core task in many applications that involve visual inspection or camera surveillance. Existing change-detection approaches suffer from three major limitations: (1) lack of evaluation on image pairs that contain no changes leading to unreported false positive rates; (2) lack of correspondences (i.e. localizing the regions before and after a change); and (3) poor zero-shot generalization across different domains. To address these issues we introduce a novel method that leverages change correspondences (a) during training to improve change detection accuracy and (b) at test time to minimize false positives. That is we harness the supervision labels of where an object is added or removed to supervise change detectors improving their accuracy over previous work [21] by a large margin. Our work is also the first to predict correspondences between pairs of detected changes using estimated homography and the Hungarian algorithm. Our model demonstrates superior performance over existing methods achieving state-of-the-art results in change detection and change correspondence accuracy across both in-distribution and zero-shot benchmarks.