{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/hyperbolic-active-learning-for-semantic","title":"Hyperbolic Active Learning for Semantic Segmentation under Domain Shift","arxiv_id":"2306.11180","date":"2023-06-19","proceeding":null,"authors":["Luca Franco","Paolo Mandica","Konstantinos Kallidromitis","Devin Guillory","Yu-Teng Li","Trevor Darrell","Fabio Galasso"],"abstract":"We introduce a hyperbolic neural network approach to pixel-level active learning for semantic segmentation. Analysis of the data statistics leads to a novel interpretation of the hyperbolic radius as an indicator of data scarcity. In HALO (Hyperbolic Active Learning Optimization), for the first time, we propose the use of epistemic uncertainty as a data acquisition strategy, following the intuition of selecting data points that are the least known. The hyperbolic radius, complemented by the widely-adopted prediction entropy, effectively approximates epistemic uncertainty. We perform extensive experimental analysis based on two established synthetic-to-real benchmarks, i.e. GTAV $\\rightarrow$ Cityscapes and SYNTHIA $\\rightarrow$ Cityscapes. Additionally, we test HALO on Cityscape $\\rightarrow$ ACDC for domain adaptation under adverse weather conditions, and we benchmark both convolutional and attention-based backbones. HALO sets a new state-of-the-art in active learning for semantic segmentation under domain shift and it is the first active learning approach that surpasses the performance of supervised domain adaptation while using only a small portion of labels (i.e., 1%).","url_abs":"https://arxiv.org/abs/2306.11180v5","url_pdf":"https://arxiv.org/pdf/2306.11180v5.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"abstracts"},"code_links":[{"paper_slug":"hyperbolic-active-learning-for-semantic","repo_url":"https://github.com/paolomandica/HALO","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":1,"framework":"pytorch","reach":null}],"tasks":[{"task_slug":"domain-adaptation","task_name":"Domain Adaptation"},{"task_slug":"semantic-segmentation","task_name":"Semantic Segmentation"},{"task_slug":"source-free-domain-adaptation","task_name":"Source-Free Domain Adaptation"}],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[{"leaderboard":"/sota/domain-adaptation-on-cityscapes-to-acdc","task":"Domain Adaptation","dataset":"Cityscapes to ACDC","model":"HALO","rank_in_archive_order":5,"of":16,"metrics":{"mIoU":"71.9"},"uses_additional_data":false},{"leaderboard":"/sota/domain-adaptation-on-gta5-to-cityscapes","task":"Domain Adaptation","dataset":"GTA5 to Cityscapes","model":"HALO","rank_in_archive_order":1,"of":28,"metrics":{"mIoU":"77.8"},"uses_additional_data":true},{"leaderboard":"/sota/domain-adaptation-on-synthia-to-cityscapes","task":"Domain Adaptation","dataset":"SYNTHIA-to-Cityscapes","model":"HALO","rank_in_archive_order":1,"of":33,"metrics":{"Extra Manual Annotation":"Yes","mIoU":"78.1"},"uses_additional_data":false},{"leaderboard":"/sota/semantic-segmentation-on-cityscapes-val","task":"Semantic Segmentation","dataset":"Cityscapes val","model":"HALO","rank_in_archive_order":64,"of":99,"metrics":{"mIoU":"77.8"},"uses_additional_data":false},{"leaderboard":"/sota/source-free-domain-adaptation-on-gta5-to","task":"Source-Free Domain Adaptation","dataset":"GTA5 to Cityscapes","model":"HALO","rank_in_archive_order":1,"of":1,"metrics":{"mIoU":"73.3"},"uses_additional_data":false}],"syntology":{"syntology_url":null,"atlas_url":"https://app.syntology.ai/?focus=2306.11180","mcp":{"get_harvested_code_for_paper":{"arxiv_id":"2306.11180"}},"developers":"https://syntology.ai/developers","read_at":"2026-09-24T18:15:14+00:00","read_at_is":"when the build read Syntology's graph, not when any sample ran","claim":"Per-sample execution status on synthesized fixtures; not a correctness claim about the paper. Samples come from repositories linked to the paper, official or community; repo_kind says which.","repos":[{"provenance":"external:paperswithcode_snapshot_2025-07-28","url":"https://github.com/paolomandica/HALO","reach":null}],"summary":{"ran_honours":2,"ran_draft_wrong":1,"unverified":5},"by_repo_kind":{"official":{"samples":8,"ran":3,"repositories":1}},"repo_kind_vocabulary":{"official":"The archive marks this repository official for the paper","named_in_paper":"The archive records that the paper mentions this repository; it is not marked official","listed":"In the archive's code links for this paper, not marked official and not recorded as mentioned in the paper","found_in_text":"Syntology found this repository in the paper's own text; whether it is the authors' implementation is not asserted","community":"Not in the archive's code links for this paper; a community repository Syntology harvested"},"n_pointer_only_for_licence":0,"samples":[{"code_sha256_prefix":"3ae23f8e61562cc3","entry":"normalize_map","repo":"paolomandica/HALO","repo_kind":"official","path":"core/active/build.py","file_url":"https://github.com/paolomandica/HALO/blob/HEAD/core/active/build.py","link_basis":"first_harvest_node","language":"python","status":"ran_honours","verification_level":1,"contract_check":"HONOURS","metamorphic_tier":null,"behaviour_fingerprint":true,"licence":"MIT","inline_ok":true,"mcp_get_code":{"code_sha256":"3ae23f8e61562cc3"}},{"code_sha256_prefix":"86d1926012f68faa","entry":"select_pixels_to_label","repo":"paolomandica/HALO","repo_kind":"official","path":"core/active/build.py","file_url":"https://github.com/paolomandica/HALO/blob/HEAD/core/active/build.py","link_basis":"first_harvest_node","language":"python","status":"ran_draft_wrong","verification_level":1,"contract_check":"MISDECLARED","metamorphic_tier":null,"behaviour_fingerprint":true,"licence":"MIT","inline_ok":true,"mcp_get_code":{"code_sha256":"86d1926012f68faa"}},{"code_sha256_prefix":"fec2f2f8d93d1fa8","entry":"to_np_array","repo":"paolomandica/HALO","repo_kind":"official","path":"core/active/build.py","file_url":"https://github.com/paolomandica/HALO/blob/HEAD/core/active/build.py","link_basis":"first_harvest_node","language":"python","status":"ran_honours","verification_level":1,"contract_check":"HONOURS","metamorphic_tier":"invariant","behaviour_fingerprint":true,"licence":"MIT","inline_ok":true,"mcp_get_code":{"code_sha256":"fec2f2f8d93d1fa8"}},{"code_sha256_prefix":"eab1d6b272518010","entry":"FloatingRegionScore","repo":"paolomandica/HALO","repo_kind":"official","path":"core/active/build.py","file_url":"https://github.com/paolomandica/HALO/blob/HEAD/core/active/build.py","link_basis":"first_harvest_node","language":"python","status":"unverified","verification_level":0,"contract_check":null,"metamorphic_tier":null,"behaviour_fingerprint":false,"licence":"MIT","inline_ok":true,"mcp_get_code":{"code_sha256":"eab1d6b272518010"}},{"code_sha256_prefix":"3e033d4c609ee08a","entry":"HyperMapper","repo":"paolomandica/HALO","repo_kind":"official","path":"core/active/build.py","file_url":"https://github.com/paolomandica/HALO/blob/HEAD/core/active/build.py","link_basis":"first_harvest_node","language":"python","status":"unverified","verification_level":0,"contract_check":null,"metamorphic_tier":null,"behaviour_fingerprint":false,"licence":"MIT","inline_ok":true,"mcp_get_code":{"code_sha256":"3e033d4c609ee08a"}},{"code_sha256_prefix":"accfc8d80e6e1e15","entry":"RegionSelection","repo":"paolomandica/HALO","repo_kind":"official","path":"core/active/build.py","file_url":"https://github.com/paolomandica/HALO/blob/HEAD/core/active/build.py","link_basis":"first_harvest_node","language":"python","status":"unverified","verification_level":0,"contract_check":null,"metamorphic_tier":null,"behaviour_fingerprint":false,"licence":"MIT","inline_ok":true,"mcp_get_code":{"code_sha256":"accfc8d80e6e1e15"}},{"code_sha256_prefix":"376c19d52db9551b","entry":"init_conv_layer","repo":"paolomandica/HALO","repo_kind":"official","path":"core/active/build.py","file_url":"https://github.com/paolomandica/HALO/blob/HEAD/core/active/build.py","link_basis":"first_harvest_node","language":"python","status":"unverified","verification_level":0,"contract_check":null,"metamorphic_tier":null,"behaviour_fingerprint":false,"licence":"MIT","inline_ok":true,"mcp_get_code":{"code_sha256":"376c19d52db9551b"}},{"code_sha256_prefix":"55135699ac9f4cd8","entry":"visualization_plots","repo":"paolomandica/HALO","repo_kind":"official","path":"core/active/build.py","file_url":"https://github.com/paolomandica/HALO/blob/HEAD/core/active/build.py","link_basis":"first_harvest_node","language":"python","status":"unverified","verification_level":0,"contract_check":null,"metamorphic_tier":null,"behaviour_fingerprint":false,"licence":"MIT","inline_ok":true,"mcp_get_code":{"code_sha256":"55135699ac9f4cd8"}}]},"arxiv_metadata":null,"syntology_extracted_results":null}