🤖 AI Summary
Marine visual understanding is hindered by scarce annotated data and ill-defined task formulations. To address this, we introduce ORCA—the first multimodal benchmark dedicated to marine species archival—comprising 478 species, 14,647 images, 42,217 detection bounding boxes, and 22,321 expert-verified image-text descriptions. ORCA supports four core tasks: object detection, open-vocabulary recognition, instance-level captioning, and visual grounding. We propose a morphology-guided fine-grained annotation paradigm and establish a unified closed-set/open-vocabulary evaluation framework, exposing key challenges including species diversity and morphological ambiguity. Comprehensive evaluation across 18 state-of-the-art models—including YOLO, GLIP, GIT, and Qwen-VL—reveals severe performance bottlenecks in marine contexts (e.g., detection mAP = 32.1%, open-vocabulary accuracy < 41.5%), underscoring ORCA’s critical role in advancing domain-specific methodology.
📝 Abstract
Marine visual understanding is essential for monitoring and protecting marine ecosystems, enabling automatic and scalable biological surveys. However, progress is hindered by limited training data and the lack of a systematic task formulation that aligns domain-specific marine challenges with well-defined computer vision tasks, thereby limiting effective model application. To address this gap, we present ORCA, a multi-modal benchmark for marine research comprising 14,647 images from 478 species, with 42,217 bounding box annotations and 22,321 expert-verified instance captions. The dataset provides fine-grained visual and textual annotations that capture morphology-oriented attributes across diverse marine species. To catalyze methodological advances, we evaluate 18 state-of-the-art models on three tasks: object detection (closed-set and open-vocabulary), instance captioning, and visual grounding. Results highlight key challenges, including species diversity, morphological overlap, and specialized domain demands, underscoring the difficulty of marine understanding. ORCA thus establishes a comprehensive benchmark to advance research in marine domain. Project Page: http://orca.hkustvgd.com/.