Diagnosing Human-Object Interaction Detectors

We have witnessed significant progress in human-object interaction (HOI) detection. However, relying solely on mAP (mean Average Precision) scores as a summary metric does not provide sufficient insight into the nuances of model performance (e.g., why one model outperforms another), which can hinder further innovation in this field. To address this issue, we introduce a diagnosis toolbox in this paper to offer a detailed quantitative breakdown of HOI detection models, inspired by the success of object detection diagnosis tools. We first conduct a holistic investigation into the HOI detection pipeline. By defining a set of errors and using oracles to fix each one, we quantitatively analyze the significance of different errors based on the mAP improvement gained from fixing them. Next, we explore the two key sub-tasks of HOI detection: human-object pair localization and interaction classification. For the pair localization task, we compute the coverage of ground-truth human-object pairs and assess the noisiness of the localization results. For the classification task, we measure a model’s ability to distinguish between positive and negative detection results and to classify actual interactions when human-object pairs are correctly localized. We analyze eight state-of-the-art HOI detection models, providing valuable diagnostic insights to guide future research. For instance, our diagnosis reveals that the state-of-the-art model RLIPv2 outperforms others primarily due to its significant improvement in multi-label interaction classification accuracy. Our toolbox is applicable across various methods and datasets and is available at https://neu-vi.github.io/Diag-HOI/.