{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2015:OXY24UVOBWPPQ3CXEY3EZNCIQX","short_pith_number":"pith:OXY24UVO","canonical_record":{"source":{"id":"1506.06006","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2015-06-19T14:01:24Z","cross_cats_sorted":[],"title_canon_sha256":"5c7b5c01e1fac94d11e0aa84e26f5ad901464da9beded3db27cd05e65ebd5780","abstract_canon_sha256":"a273dc7f019f4e06283db8df52a95dd4f9d7ae6fece4c2b2e92c245b0e24784d"},"schema_version":"1.0"},"canonical_sha256":"75f1ae52ae0d9ef86c5726364cb44885db9de2c26331aec9efb70943411d57e9","source":{"kind":"arxiv","id":"1506.06006","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1506.06006","created_at":"2026-05-18T01:42:46Z"},{"alias_kind":"arxiv_version","alias_value":"1506.06006v1","created_at":"2026-05-18T01:42:46Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1506.06006","created_at":"2026-05-18T01:42:46Z"},{"alias_kind":"pith_short_12","alias_value":"OXY24UVOBWPP","created_at":"2026-05-18T12:29:34Z"},{"alias_kind":"pith_short_16","alias_value":"OXY24UVOBWPPQ3CX","created_at":"2026-05-18T12:29:34Z"},{"alias_kind":"pith_short_8","alias_value":"OXY24UVO","created_at":"2026-05-18T12:29:34Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2015:OXY24UVOBWPPQ3CXEY3EZNCIQX","target":"record","payload":{"canonical_record":{"source":{"id":"1506.06006","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2015-06-19T14:01:24Z","cross_cats_sorted":[],"title_canon_sha256":"5c7b5c01e1fac94d11e0aa84e26f5ad901464da9beded3db27cd05e65ebd5780","abstract_canon_sha256":"a273dc7f019f4e06283db8df52a95dd4f9d7ae6fece4c2b2e92c245b0e24784d"},"schema_version":"1.0"},"canonical_sha256":"75f1ae52ae0d9ef86c5726364cb44885db9de2c26331aec9efb70943411d57e9","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:42:46.504532Z","signature_b64":"4GH0GcsYa8/BSOHXEVQJzVx8bubrrjwVcjrEJpYSPhG8XSIqjGduVfWg9VuTs4D5HMI2X8RywY3eeVZO+PsMCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"75f1ae52ae0d9ef86c5726364cb44885db9de2c26331aec9efb70943411d57e9","last_reissued_at":"2026-05-18T01:42:46.504038Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:42:46.504038Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1506.06006","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:42:46Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"INaxNe15J+VbcxScm7vwuGKgfv6z+1hNiba9LQGE9s5euJNyc49M1Y89arpBI/qxZ5qibPUErCXMq8T4XsHfDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-30T16:10:47.365193Z"},"content_sha256":"44ebe4ab1e87423ff76dc85ff27cfaf870bc288fb99552ebcae180f6d978c3b0","schema_version":"1.0","event_id":"sha256:44ebe4ab1e87423ff76dc85ff27cfaf870bc288fb99552ebcae180f6d978c3b0"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2015:OXY24UVOBWPPQ3CXEY3EZNCIQX","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Crowd Flow Segmentation in Compressed Domain using CRF","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.CV","authors_text":"R. Venkatesh Babu, Srinivas S. S. Kruthiventi","submitted_at":"2015-06-19T14:01:24Z","abstract_excerpt":"Crowd flow segmentation is an important step in many video surveillance tasks. In this work, we propose an algorithm for segmenting flows in H.264 compressed videos in a completely unsupervised manner. Our algorithm works on motion vectors which can be obtained by partially decoding the compressed video without extracting any additional features. Our approach is based on modelling the motion vector field as a Conditional Random Field (CRF) and obtaining oriented motion segments by finding the optimal labelling which minimises the global energy of CRF. These oriented motion segments are recursi"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1506.06006","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:42:46Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"4oKKHv3racGSJn6QCamP7OOtlJUeUw6Nn6uRkv9ozTnn6iZCJqFNF41arLZs5gNPC3qU82x9aB0bPws4PJNvCg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-30T16:10:47.365553Z"},"content_sha256":"fd3729da2c86b7b9f5381efa6bc08baaf7be4c5c64fe176599e9b5cdc8722fcc","schema_version":"1.0","event_id":"sha256:fd3729da2c86b7b9f5381efa6bc08baaf7be4c5c64fe176599e9b5cdc8722fcc"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/OXY24UVOBWPPQ3CXEY3EZNCIQX/bundle.json","state_url":"https://pith.science/pith/OXY24UVOBWPPQ3CXEY3EZNCIQX/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/OXY24UVOBWPPQ3CXEY3EZNCIQX/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-06-30T16:10:47Z","links":{"resolver":"https://pith.science/pith/OXY24UVOBWPPQ3CXEY3EZNCIQX","bundle":"https://pith.science/pith/OXY24UVOBWPPQ3CXEY3EZNCIQX/bundle.json","state":"https://pith.science/pith/OXY24UVOBWPPQ3CXEY3EZNCIQX/state.json","well_known_bundle":"https://pith.science/.well-known/pith/OXY24UVOBWPPQ3CXEY3EZNCIQX/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2015:OXY24UVOBWPPQ3CXEY3EZNCIQX","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"a273dc7f019f4e06283db8df52a95dd4f9d7ae6fece4c2b2e92c245b0e24784d","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2015-06-19T14:01:24Z","title_canon_sha256":"5c7b5c01e1fac94d11e0aa84e26f5ad901464da9beded3db27cd05e65ebd5780"},"schema_version":"1.0","source":{"id":"1506.06006","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1506.06006","created_at":"2026-05-18T01:42:46Z"},{"alias_kind":"arxiv_version","alias_value":"1506.06006v1","created_at":"2026-05-18T01:42:46Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1506.06006","created_at":"2026-05-18T01:42:46Z"},{"alias_kind":"pith_short_12","alias_value":"OXY24UVOBWPP","created_at":"2026-05-18T12:29:34Z"},{"alias_kind":"pith_short_16","alias_value":"OXY24UVOBWPPQ3CX","created_at":"2026-05-18T12:29:34Z"},{"alias_kind":"pith_short_8","alias_value":"OXY24UVO","created_at":"2026-05-18T12:29:34Z"}],"graph_snapshots":[{"event_id":"sha256:fd3729da2c86b7b9f5381efa6bc08baaf7be4c5c64fe176599e9b5cdc8722fcc","target":"graph","created_at":"2026-05-18T01:42:46Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"Crowd flow segmentation is an important step in many video surveillance tasks. In this work, we propose an algorithm for segmenting flows in H.264 compressed videos in a completely unsupervised manner. Our algorithm works on motion vectors which can be obtained by partially decoding the compressed video without extracting any additional features. Our approach is based on modelling the motion vector field as a Conditional Random Field (CRF) and obtaining oriented motion segments by finding the optimal labelling which minimises the global energy of CRF. These oriented motion segments are recursi","authors_text":"R. Venkatesh Babu, Srinivas S. S. Kruthiventi","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2015-06-19T14:01:24Z","title":"Crowd Flow Segmentation in Compressed Domain using CRF"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1506.06006","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:44ebe4ab1e87423ff76dc85ff27cfaf870bc288fb99552ebcae180f6d978c3b0","target":"record","created_at":"2026-05-18T01:42:46Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"a273dc7f019f4e06283db8df52a95dd4f9d7ae6fece4c2b2e92c245b0e24784d","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2015-06-19T14:01:24Z","title_canon_sha256":"5c7b5c01e1fac94d11e0aa84e26f5ad901464da9beded3db27cd05e65ebd5780"},"schema_version":"1.0","source":{"id":"1506.06006","kind":"arxiv","version":1}},"canonical_sha256":"75f1ae52ae0d9ef86c5726364cb44885db9de2c26331aec9efb70943411d57e9","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"75f1ae52ae0d9ef86c5726364cb44885db9de2c26331aec9efb70943411d57e9","first_computed_at":"2026-05-18T01:42:46.504038Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:42:46.504038Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"4GH0GcsYa8/BSOHXEVQJzVx8bubrrjwVcjrEJpYSPhG8XSIqjGduVfWg9VuTs4D5HMI2X8RywY3eeVZO+PsMCA==","signature_status":"signed_v1","signed_at":"2026-05-18T01:42:46.504532Z","signed_message":"canonical_sha256_bytes"},"source_id":"1506.06006","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:44ebe4ab1e87423ff76dc85ff27cfaf870bc288fb99552ebcae180f6d978c3b0","sha256:fd3729da2c86b7b9f5381efa6bc08baaf7be4c5c64fe176599e9b5cdc8722fcc"],"state_sha256":"e4ae4183c861616980d55d815bb2ab11e76b6ca48fc9d38b1eec3b9bb08b9a64"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"+PBS3LUxtOf4dt12hZq0d8Wy+CLdqV2fw/mbM83Bzqa9uQKpSEyj4f6N4Nh8q4XTxhaKFONEzFxTrs9XuV9TBQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-30T16:10:47.368008Z","bundle_sha256":"0b9feca3b0d55dd65455ae59f0c97217c423aaf30bc53171d808b4ebbc3c8879"}}