{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:JFKXU2NNZWJL67TDWWH6UG7HS6","short_pith_number":"pith:JFKXU2NN","canonical_record":{"source":{"id":"1903.08827","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2019-03-21T04:37:55Z","cross_cats_sorted":[],"title_canon_sha256":"243f021eeee8618da18e4a7aab8fac67a931c9fc9a570b49f0a2720c8f67fe73","abstract_canon_sha256":"86206fcdb1a2fff814eb773487940d23dc93bc70c3cf61a0c6aaa217e0693031"},"schema_version":"1.0"},"canonical_sha256":"49557a69adcd92bf7e63b58fea1be797bb89d704ff77c17c1f308f5033756f37","source":{"kind":"arxiv","id":"1903.08827","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1903.08827","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"arxiv_version","alias_value":"1903.08827v1","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1903.08827","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"pith_short_12","alias_value":"JFKXU2NNZWJL","created_at":"2026-05-18T12:33:21Z"},{"alias_kind":"pith_short_16","alias_value":"JFKXU2NNZWJL67TD","created_at":"2026-05-18T12:33:21Z"},{"alias_kind":"pith_short_8","alias_value":"JFKXU2NN","created_at":"2026-05-18T12:33:21Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:JFKXU2NNZWJL67TDWWH6UG7HS6","target":"record","payload":{"canonical_record":{"source":{"id":"1903.08827","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2019-03-21T04:37:55Z","cross_cats_sorted":[],"title_canon_sha256":"243f021eeee8618da18e4a7aab8fac67a931c9fc9a570b49f0a2720c8f67fe73","abstract_canon_sha256":"86206fcdb1a2fff814eb773487940d23dc93bc70c3cf61a0c6aaa217e0693031"},"schema_version":"1.0"},"canonical_sha256":"49557a69adcd92bf7e63b58fea1be797bb89d704ff77c17c1f308f5033756f37","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:50:43.813212Z","signature_b64":"wKXJpVE8IhBDtJmFhTi75t3UuESMw11MayRKPXtEzm1AUKKtRWQ3J1hWyXN2Nd4TKCNxkF+Qn26+AxmueGTZAg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"49557a69adcd92bf7e63b58fea1be797bb89d704ff77c17c1f308f5033756f37","last_reissued_at":"2026-05-17T23:50:43.812583Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:50:43.812583Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1903.08827","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":"2026-05-17T23:50:43Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"tH9A1HrsjbgRjbkLSwvk1H+Ibu3WoVXf2BHoCN7ycSH3FMV1gF5tnXLmqKCh/3hmZT4O0s7q56Rt6V7gPIhJAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-07T16:43:22.255909Z"},"content_sha256":"e9f0879f25d6a41d2e1b786a251eadeaf08b183092737e76d38358a10dd65800","schema_version":"1.0","event_id":"sha256:e9f0879f25d6a41d2e1b786a251eadeaf08b183092737e76d38358a10dd65800"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:JFKXU2NNZWJL67TDWWH6UG7HS6","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"What's in a frequency: new tools for graph Fourier Transform visualization","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"eess.SP","authors_text":"Antonio Ortega, Benjamin Girault","submitted_at":"2019-03-21T04:37:55Z","abstract_excerpt":"Recent progress in graph signal processing (GSP) has addressed a number of problems, including sampling and filtering. Proposed methods have focused on generic graphs and defined signals with certain characteristics, e.g., bandlimited signals, based on t he graph Fourier transform (GFT). However, the effect of GFT properties (e.g., vertex localization) on the behavior of such methods is not as well understood. In this paper, we propose novel GFT visualization tools and provide some examples to illustrate certain GFT properties and their impact on sampling or wavelet transforms."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1903.08827","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":"2026-05-17T23:50:43Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"shBccQTM9WBBgDENfoC08NsCl32OMWeMJquoIK2yy9ivBNjz7WByXJWyc9axGKjeLFJTUCim4pr/W9snhxDaCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-07T16:43:22.256575Z"},"content_sha256":"9e521d1e5b9ad78fd02a6bd6df3d7034d6cc977a4d52c5004b165706e948706a","schema_version":"1.0","event_id":"sha256:9e521d1e5b9ad78fd02a6bd6df3d7034d6cc977a4d52c5004b165706e948706a"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/JFKXU2NNZWJL67TDWWH6UG7HS6/bundle.json","state_url":"https://pith.science/pith/JFKXU2NNZWJL67TDWWH6UG7HS6/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/JFKXU2NNZWJL67TDWWH6UG7HS6/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":"2026-06-07T16:43:22Z","links":{"resolver":"https://pith.science/pith/JFKXU2NNZWJL67TDWWH6UG7HS6","bundle":"https://pith.science/pith/JFKXU2NNZWJL67TDWWH6UG7HS6/bundle.json","state":"https://pith.science/pith/JFKXU2NNZWJL67TDWWH6UG7HS6/state.json","well_known_bundle":"https://pith.science/.well-known/pith/JFKXU2NNZWJL67TDWWH6UG7HS6/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:JFKXU2NNZWJL67TDWWH6UG7HS6","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":"86206fcdb1a2fff814eb773487940d23dc93bc70c3cf61a0c6aaa217e0693031","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2019-03-21T04:37:55Z","title_canon_sha256":"243f021eeee8618da18e4a7aab8fac67a931c9fc9a570b49f0a2720c8f67fe73"},"schema_version":"1.0","source":{"id":"1903.08827","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1903.08827","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"arxiv_version","alias_value":"1903.08827v1","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1903.08827","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"pith_short_12","alias_value":"JFKXU2NNZWJL","created_at":"2026-05-18T12:33:21Z"},{"alias_kind":"pith_short_16","alias_value":"JFKXU2NNZWJL67TD","created_at":"2026-05-18T12:33:21Z"},{"alias_kind":"pith_short_8","alias_value":"JFKXU2NN","created_at":"2026-05-18T12:33:21Z"}],"graph_snapshots":[{"event_id":"sha256:9e521d1e5b9ad78fd02a6bd6df3d7034d6cc977a4d52c5004b165706e948706a","target":"graph","created_at":"2026-05-17T23:50:43Z","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":"Recent progress in graph signal processing (GSP) has addressed a number of problems, including sampling and filtering. Proposed methods have focused on generic graphs and defined signals with certain characteristics, e.g., bandlimited signals, based on t he graph Fourier transform (GFT). However, the effect of GFT properties (e.g., vertex localization) on the behavior of such methods is not as well understood. In this paper, we propose novel GFT visualization tools and provide some examples to illustrate certain GFT properties and their impact on sampling or wavelet transforms.","authors_text":"Antonio Ortega, Benjamin Girault","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2019-03-21T04:37:55Z","title":"What's in a frequency: new tools for graph Fourier Transform visualization"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1903.08827","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:e9f0879f25d6a41d2e1b786a251eadeaf08b183092737e76d38358a10dd65800","target":"record","created_at":"2026-05-17T23:50:43Z","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":"86206fcdb1a2fff814eb773487940d23dc93bc70c3cf61a0c6aaa217e0693031","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2019-03-21T04:37:55Z","title_canon_sha256":"243f021eeee8618da18e4a7aab8fac67a931c9fc9a570b49f0a2720c8f67fe73"},"schema_version":"1.0","source":{"id":"1903.08827","kind":"arxiv","version":1}},"canonical_sha256":"49557a69adcd92bf7e63b58fea1be797bb89d704ff77c17c1f308f5033756f37","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"49557a69adcd92bf7e63b58fea1be797bb89d704ff77c17c1f308f5033756f37","first_computed_at":"2026-05-17T23:50:43.812583Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:50:43.812583Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"wKXJpVE8IhBDtJmFhTi75t3UuESMw11MayRKPXtEzm1AUKKtRWQ3J1hWyXN2Nd4TKCNxkF+Qn26+AxmueGTZAg==","signature_status":"signed_v1","signed_at":"2026-05-17T23:50:43.813212Z","signed_message":"canonical_sha256_bytes"},"source_id":"1903.08827","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:e9f0879f25d6a41d2e1b786a251eadeaf08b183092737e76d38358a10dd65800","sha256:9e521d1e5b9ad78fd02a6bd6df3d7034d6cc977a4d52c5004b165706e948706a"],"state_sha256":"cc2a924cd3d2f59cebc131e18758d32e0a628d65cb45fdcbe71925f77f53cedb"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"U6kHj6SfMuKLIueVeEPzwpYdLfTYjN3rMugsAmVo5IGgZfi5y3X8hut4I3mO7rRIduCcaiNf1WN8aDIHY6U+CQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-07T16:43:22.259953Z","bundle_sha256":"841ea5f1fbc7e91314ddd591b9d036bc533375dca7205ca9ccf18217f8d8e2f5"}}