Papers › BiSeNet V2: Bilateral Network with Guided Aggregation for Real-time Semantic Segmentation

BiSeNet V2: Bilateral Network with Guided Aggregation for Real-time Semantic Segmentation

5 Apr 2020arXiv:2004.02147archive 2025-07-28

Changqian Yu, Changxin Gao, Jingbo Wang, Gang Yu, Chunhua Shen, Nong Sang

The low-level details and high-level semantics are both essential to the semantic segmentation task. However, to speed up the model inference, current approaches almost always sacrifice the low-level details, which leads to a considerable accuracy decrease. We propose to treat these spatial details and categorical semantics separately to achieve high accuracy and high efficiency for realtime semantic segmentation. To this end, we propose an efficient and effective architecture with a good trade-off between speed and accuracy, termed Bilateral Segmentation Network (BiSeNet V2). This architecture involves: (i) a Detail Branch, with wide channels and shallow layers to capture low-level details and generate high-resolution feature representation; (ii) a Semantic Branch, with narrow channels and deep layers to obtain high-level semantic context. The Semantic Branch is lightweight due to reducing the channel capacity and a fast-downsampling strategy. Furthermore, we design a Guided Aggregation Layer to enhance mutual connections and fuse both types of feature representation. Besides, a booster training strategy is designed to improve the segmentation performance without any extra inference cost. Extensive quantitative and qualitative evaluations demonstrate that the proposed architecture performs favourably against a few state-of-the-art real-time semantic segmentation approaches. Specifically, for a 2,048x1,024 input, we achieve 72.6% Mean IoU on the Cityscapes test set with a speed of 156 FPS on one NVIDIA GeForce GTX 1080 Ti card, which is significantly faster than existing methods, yet we achieve better segmentation accuracy.

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Code

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CoinCheung/BiSeNet mentioned on GitHubpytorch report
hamidriasat/BiSeNetV2 mentioned on GitHubtfMIT report
ycszen/BiSeNet mentioned on GitHub report

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Code Syntology ran Syntology

10 samples harvested; 7 ran; 2 honoured the contract we drafted; 3 have no recorded run. Read from Syntology's graph 2026-09-25; that is when this build read the record, not when the samples ran.

2ran · honoured contract
3ran · violated contract
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calc_bd gymoon10/Instance-Segmentation-with-SpatialEmbedding-CA/src/evaluation.py community (archive-listed) ran · honoured contract fingerprinted no licence file found · pointer only · ad8c528f7eca3b49 · report
calc_dic gymoon10/Instance-Segmentation-with-SpatialEmbedding-CA/src/evaluation.py community (archive-listed) ran · violated contract fingerprinted no licence file found · pointer only · 1178cc4faa78d246 · report
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compute_iou MaybeShewill-CV/bisenetv2-tensorflow/tools/cityscapes/test_bisenetv2_cityscapes.py community (archive-listed) ran · fixture could not drive it fingerprinted MIT (permissive) · 4c9edc2f665fa3ba · report
decode_prediction_mask MaybeShewill-CV/bisenetv2-tensorflow/tools/cityscapes/test_bisenetv2_cityscapes.py community (archive-listed) ran · honoured contract fingerprinted MIT (permissive) · f28994d15f099406 · report
stem_block hamidriasat/BiSeNetV2/bisenet_v2.py community (archive-listed) ran fingerprinted MIT (permissive) · cda3c7e994899232 · report
context_embedding_block hamidriasat/BiSeNetV2/bisenet_v2.py community (archive-listed) unverified MIT (permissive) · 6ecfb144dedc8a7a · report
gather_and_expansion_layer hamidriasat/BiSeNetV2/bisenet_v2.py community (archive-listed) unverified MIT (permissive) · bb4d9fdc1dc610e5 · report
args_str2bool identical code first harvested elsewhere ran · violated contract licence of this copy not recorded · eba8919c2ae4a92f · report
set_model_dist identical code first harvested elsewhere unverified licence of this copy not recorded · 5c1d86977d83a6be · report

Tasks

Real-Time Semantic SegmentationSegmentationSemantic Segmentation

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Real-Time Semantic Segmentation COCO-Stuff BiSeNet V2-Large Frame (fps) 42.5(1080Ti) #1 of 2 Archive leaderboard report
Real-Time Semantic Segmentation COCO-Stuff BiSeNet V2-Large mIoU 28.7 #1 of 2 Archive leaderboard report
Real-Time Semantic Segmentation COCO-Stuff BiSeNet V2 Frame (fps) 87.9(1080Ti) #2 of 2 Archive leaderboard report
Real-Time Semantic Segmentation COCO-Stuff BiSeNet V2 mIoU 25.2 #2 of 2 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2-Large(Cityscapes-Pretrained) Frame (fps) 32.7 #8 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2-Large(Cityscapes-Pretrained) Time (ms) 30.6 #8 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2-Large(Cityscapes-Pretrained) mIoU 78.5 #8 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2(Cityscapes-Pretrained) Frame (fps) 124.5 #10 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2(Cityscapes-Pretrained) Time (ms) 8.0 #10 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2(Cityscapes-Pretrained) mIoU 76.7 #10 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2-Large Frame (fps) 32.7 #17 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2-Large Time (ms) 30.6 #17 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2-Large mIoU 73.2 #17 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2 Frame (fps) 124.5 #19 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2 Time (ms) 8.0 #19 of 29 Archive leaderboard report
Real-Time Semantic Segmentation CamVid BiSeNet V2 mIoU 72.4 #19 of 29 Archive leaderboard report
Real-Time Semantic Segmentation Cityscapes test BiSeNet V2-Large Frame (fps) 47.3 #14 of 39 Archive leaderboard report
Real-Time Semantic Segmentation Cityscapes test BiSeNet V2-Large Time (ms) 21.1 #14 of 39 Archive leaderboard report
Real-Time Semantic Segmentation Cityscapes test BiSeNet V2-Large mIoU 75.3% #14 of 39 Archive leaderboard report
Real-Time Semantic Segmentation Cityscapes test BiSeNet V2 Frame (fps) 156 #23 of 39 Archive leaderboard report
Real-Time Semantic Segmentation Cityscapes test BiSeNet V2 Time (ms) 6.4 #23 of 39 Archive leaderboard report
Real-Time Semantic Segmentation Cityscapes test BiSeNet V2 mIoU 72.6% #23 of 39 Archive leaderboard report
Real-Time Semantic Segmentation Cityscapes val BiseNetV2-L Frame (fps) 47.3 #15 of 24 Archive leaderboard report
Real-Time Semantic Segmentation Cityscapes val BiseNetV2-L mIoU 75.8% #15 of 24 Archive leaderboard report
Real-Time Semantic Segmentation Cityscapes val BiseNetV2 Frame (fps) 156 #20 of 24 Archive leaderboard report
Real-Time Semantic Segmentation Cityscapes val BiseNetV2 mIoU 73.5% #20 of 24 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.

Methods

Introduced by this paper: BiSeNet V2, Bilateral Guided Aggregation Layer

1x1 ConvolutionAverage PoolingBatch NormalizationBiSeNet V2Bilateral Guided Aggregation LayerConvolutionDepthwise ConvolutionReLUResidual ConnectionSPEED

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