{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2020:ZDR464K22M2QLD25CQIOZEYJC2","short_pith_number":"pith:ZDR464K2","schema_version":"1.0","canonical_sha256":"c8e3cf715ad335058f5d1410ec9309169fcc825f1ae1b0011c33c368738671b3","source":{"kind":"arxiv","id":"2002.11812","version":2},"attestation_state":"computed","paper":{"title":"Learning to Shadow Hand-drawn Sketches","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cs.GR","cs.MM"],"primary_cat":"cs.CV","authors_text":"Adam Bargteil, Qingyuan Zheng, Zhuoru Li","submitted_at":"2020-02-26T21:57:17Z","abstract_excerpt":"We present a fully automatic method to generate detailed and accurate artistic shadows from pairs of line drawing sketches and lighting directions. We also contribute a new dataset of one thousand examples of pairs of line drawings and shadows that are tagged with lighting directions. Remarkably, the generated shadows quickly communicate the underlying 3D structure of the sketched scene. Consequently, the shadows generated by our approach can be used directly or as an excellent starting point for artists. We demonstrate that the deep learning network we propose takes a hand-drawn sketch, build"},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"2002.11812","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2020-02-26T21:57:17Z","cross_cats_sorted":["cs.GR","cs.MM"],"title_canon_sha256":"7eca7f2e5c20bc22bbdd000ba6ec71b3bbedcc415cad7b7348d9e7696d0fd7be","abstract_canon_sha256":"4765d085cb406e400239e01b284e81d4710ab4f8c0c38cff7d48b3c3ea7c2c50"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T00:52:30.146126Z","signature_b64":"1yYQJx/5KnKE0/yHdahpJTxHQTUAV+yVdnvzMPkRhChanX2WRvdpS99ZH+5FNNTXU1AOTaPCJ9wtlaKzRppBCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"c8e3cf715ad335058f5d1410ec9309169fcc825f1ae1b0011c33c368738671b3","last_reissued_at":"2026-07-05T00:52:30.145455Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T00:52:30.145455Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Learning to Shadow Hand-drawn Sketches","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cs.GR","cs.MM"],"primary_cat":"cs.CV","authors_text":"Adam Bargteil, Qingyuan Zheng, Zhuoru Li","submitted_at":"2020-02-26T21:57:17Z","abstract_excerpt":"We present a fully automatic method to generate detailed and accurate artistic shadows from pairs of line drawing sketches and lighting directions. We also contribute a new dataset of one thousand examples of pairs of line drawings and shadows that are tagged with lighting directions. Remarkably, the generated shadows quickly communicate the underlying 3D structure of the sketched scene. Consequently, the shadows generated by our approach can be used directly or as an excellent starting point for artists. We demonstrate that the deep learning network we propose takes a hand-drawn sketch, build"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2002.11812","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2002.11812/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"aliases":[{"alias_kind":"arxiv","alias_value":"2002.11812","created_at":"2026-07-05T00:52:30.145532+00:00"},{"alias_kind":"arxiv_version","alias_value":"2002.11812v2","created_at":"2026-07-05T00:52:30.145532+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2002.11812","created_at":"2026-07-05T00:52:30.145532+00:00"},{"alias_kind":"pith_short_12","alias_value":"ZDR464K22M2Q","created_at":"2026-07-05T00:52:30.145532+00:00"},{"alias_kind":"pith_short_16","alias_value":"ZDR464K22M2QLD25","created_at":"2026-07-05T00:52:30.145532+00:00"},{"alias_kind":"pith_short_8","alias_value":"ZDR464K2","created_at":"2026-07-05T00:52:30.145532+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/ZDR464K22M2QLD25CQIOZEYJC2","json":"https://pith.science/pith/ZDR464K22M2QLD25CQIOZEYJC2.json","graph_json":"https://pith.science/api/pith-number/ZDR464K22M2QLD25CQIOZEYJC2/graph.json","events_json":"https://pith.science/api/pith-number/ZDR464K22M2QLD25CQIOZEYJC2/events.json","paper":"https://pith.science/paper/ZDR464K2"},"agent_actions":{"view_html":"https://pith.science/pith/ZDR464K22M2QLD25CQIOZEYJC2","download_json":"https://pith.science/pith/ZDR464K22M2QLD25CQIOZEYJC2.json","view_paper":"https://pith.science/paper/ZDR464K2","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=2002.11812&json=true","fetch_graph":"https://pith.science/api/pith-number/ZDR464K22M2QLD25CQIOZEYJC2/graph.json","fetch_events":"https://pith.science/api/pith-number/ZDR464K22M2QLD25CQIOZEYJC2/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/ZDR464K22M2QLD25CQIOZEYJC2/action/timestamp_anchor","attest_storage":"https://pith.science/pith/ZDR464K22M2QLD25CQIOZEYJC2/action/storage_attestation","attest_author":"https://pith.science/pith/ZDR464K22M2QLD25CQIOZEYJC2/action/author_attestation","sign_citation":"https://pith.science/pith/ZDR464K22M2QLD25CQIOZEYJC2/action/citation_signature","submit_replication":"https://pith.science/pith/ZDR464K22M2QLD25CQIOZEYJC2/action/replication_record"}},"created_at":"2026-07-05T00:52:30.145532+00:00","updated_at":"2026-07-05T00:52:30.145532+00:00"}