Papers › Where2comm: Communication-Efficient Collaborative Perception via Spatial Confidence Maps

Where2comm: Communication-Efficient Collaborative Perception via Spatial Confidence Maps

26 Sep 2022arXiv:2209.12836archive 2025-07-28

Yue Hu, Shaoheng Fang, Zixing Lei, Yiqi Zhong, Siheng Chen

Multi-agent collaborative perception could significantly upgrade the perception performance by enabling agents to share complementary information with each other through communication. It inevitably results in a fundamental trade-off between perception performance and communication bandwidth. To tackle this bottleneck issue, we propose a spatial confidence map, which reflects the spatial heterogeneity of perceptual information. It empowers agents to only share spatially sparse, yet perceptually critical information, contributing to where to communicate. Based on this novel spatial confidence map, we propose Where2comm, a communication-efficient collaborative perception framework. Where2comm has two distinct advantages: i) it considers pragmatic compression and uses less communication to achieve higher perception performance by focusing on perceptually critical areas; and ii) it can handle varying communication bandwidth by dynamically adjusting spatial areas involved in communication. To evaluate Where2comm, we consider 3D object detection in both real-world and simulation scenarios with two modalities (camera/LiDAR) and two agent types (cars/drones) on four datasets: OPV2V, V2X-Sim, DAIR-V2X, and our original CoPerception-UAVs. Where2comm consistently outperforms previous methods; for example, it achieves more than 100,000 × lower communication volume and still outperforms DiscoNet and V2X-ViT on OPV2V. Our code is available at https://github.com/MediaBrain-SJTU/where2comm.

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AttenFusion mediabrain-sjtu/where2comm/opencood/models/fuse_modules/where2comm_attn.py official repository ran fingerprinted no licence file found · pointer only · 6f81083e2e5d4e96 · report
Communication mediabrain-sjtu/where2comm/opencood/models/fuse_modules/where2comm_attn.py official repository ran no licence file found · pointer only · 4ec9d4b6d8dfe0f4 · report
EncodeLayer mediabrain-sjtu/where2comm/opencood/models/fuse_modules/where2comm_attn.py official repository ran no licence file found · pointer only · 9f94125b1d8e1caa · report
ScaledDotProductAttention mediabrain-sjtu/where2comm/opencood/models/fuse_modules/where2comm_attn.py official repository ran fingerprinted no licence file found · pointer only · 80dba65b5ece1488 · report
TransformerFusion mediabrain-sjtu/where2comm/opencood/models/fuse_modules/where2comm_attn.py official repository unverified no licence file found · pointer only · 9b42dff7d0e05021 · report
Where2comm mediabrain-sjtu/where2comm/opencood/models/fuse_modules/where2comm_attn.py official repository unverified no licence file found · pointer only · d697d09dc4b0b7f4 · report

Tasks

3D Object DetectionMonocular 3D Object DetectionObject Detectionobject-detection

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
3D Object Detection DAIR-V2X Where2comm AP50 63.71 #2 of 2 Archive leaderboard report
3D Object Detection V2X-SIM Where2comm mAOE 0.310 #5 of 5 Archive leaderboard report
3D Object Detection V2X-SIM Where2comm mAP 19.0 #5 of 5 Archive leaderboard report
3D Object Detection V2X-SIM Where2comm mASE 0.275 #5 of 5 Archive leaderboard report
3D Object Detection V2X-SIM Where2comm mATE 0.911 #5 of 5 Archive leaderboard report
Monocular 3D Object Detection CoPerception-UAVs Where2comm AP50 65.71 #1 of 1 Archive leaderboard report
Monocular 3D Object Detection OPV2V Where2comm AP50 47.14 #1 of 1 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

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