{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2012:OUSSQ3BWWUZLFXCNRXNW3D2XSO","short_pith_number":"pith:OUSSQ3BW","canonical_record":{"source":{"id":"1211.3659","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.GR","submitted_at":"2012-11-15T17:08:58Z","cross_cats_sorted":[],"title_canon_sha256":"ed20c909e8ed19518fb5ad59b8ab0b761369b17f7a7e7ca59858ebd1c1ed9773","abstract_canon_sha256":"f96248ab6a0c628ac84108eb8d259146bb18098907c428ac92fc58704d8fa78f"},"schema_version":"1.0"},"canonical_sha256":"7525286c36b532b2dc4d8ddb6d8f57938cdaaee49996b0467f193fdb393cca37","source":{"kind":"arxiv","id":"1211.3659","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1211.3659","created_at":"2026-05-18T03:40:39Z"},{"alias_kind":"arxiv_version","alias_value":"1211.3659v1","created_at":"2026-05-18T03:40:39Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1211.3659","created_at":"2026-05-18T03:40:39Z"},{"alias_kind":"pith_short_12","alias_value":"OUSSQ3BWWUZL","created_at":"2026-05-18T12:27:16Z"},{"alias_kind":"pith_short_16","alias_value":"OUSSQ3BWWUZLFXCN","created_at":"2026-05-18T12:27:16Z"},{"alias_kind":"pith_short_8","alias_value":"OUSSQ3BW","created_at":"2026-05-18T12:27:16Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2012:OUSSQ3BWWUZLFXCNRXNW3D2XSO","target":"record","payload":{"canonical_record":{"source":{"id":"1211.3659","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.GR","submitted_at":"2012-11-15T17:08:58Z","cross_cats_sorted":[],"title_canon_sha256":"ed20c909e8ed19518fb5ad59b8ab0b761369b17f7a7e7ca59858ebd1c1ed9773","abstract_canon_sha256":"f96248ab6a0c628ac84108eb8d259146bb18098907c428ac92fc58704d8fa78f"},"schema_version":"1.0"},"canonical_sha256":"7525286c36b532b2dc4d8ddb6d8f57938cdaaee49996b0467f193fdb393cca37","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T03:40:39.148147Z","signature_b64":"4pxid2aiw/GbxTY55O60Ib69aYRSwe6vbEQWYQBQOx7aOO464+QFL14i9fCVIfF1swRhr9S4h6jYq1kyfFcbBQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"7525286c36b532b2dc4d8ddb6d8f57938cdaaee49996b0467f193fdb393cca37","last_reissued_at":"2026-05-18T03:40:39.147306Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T03:40:39.147306Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1211.3659","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":"2026-05-18T03:40:39Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"nfpC/KhD3zk9f0exn7ETzdyhwXG7LwCUeKMMymOfHJC9M4LNDrmCGSEzXHKUHqQltibC52n53p/aYaBO0DIyCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-26T02:25:58.041213Z"},"content_sha256":"7cfe16c713e7458b331392e2df28337d07971adc59893adb06a82f36a6954075","schema_version":"1.0","event_id":"sha256:7cfe16c713e7458b331392e2df28337d07971adc59893adb06a82f36a6954075"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2012:OUSSQ3BWWUZLFXCNRXNW3D2XSO","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Color scales that are effective in both color and grayscale","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.GR","authors_text":"Silas Alben","submitted_at":"2012-11-15T17:08:58Z","abstract_excerpt":"We consider the problem of finding a color scale which performs well when converted to a grayscale. We assume that each color is converted to a shade of gray with the same intensity as the color. We also assume that the color scales have a linear variation of intensity and hue, and find scales which maximize the average chroma (or \"colorfulness\") of the colors. We find two classes of solutions, which traverse the color wheel in opposite directions. The two classes of scales start with hues near cyan and red. The average chroma of the scales are 65-77% those of the pure colors."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1211.3659","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":"2026-05-18T03:40:39Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"KkuS+Jdn7r1AlIS3K1z7m+Nk/+Kr3pM1gkdAmSPCjlsCysv/bRkE9NGrWlUKCRgx6aMUPsocqOiT114wJBeoBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-26T02:25:58.041593Z"},"content_sha256":"34c8d6575aaee3dd43e3b1e72054c5a5e9b2b6fe5397da38645891292a7c048f","schema_version":"1.0","event_id":"sha256:34c8d6575aaee3dd43e3b1e72054c5a5e9b2b6fe5397da38645891292a7c048f"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/OUSSQ3BWWUZLFXCNRXNW3D2XSO/bundle.json","state_url":"https://pith.science/pith/OUSSQ3BWWUZLFXCNRXNW3D2XSO/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/OUSSQ3BWWUZLFXCNRXNW3D2XSO/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":"2026-06-26T02:25:58Z","links":{"resolver":"https://pith.science/pith/OUSSQ3BWWUZLFXCNRXNW3D2XSO","bundle":"https://pith.science/pith/OUSSQ3BWWUZLFXCNRXNW3D2XSO/bundle.json","state":"https://pith.science/pith/OUSSQ3BWWUZLFXCNRXNW3D2XSO/state.json","well_known_bundle":"https://pith.science/.well-known/pith/OUSSQ3BWWUZLFXCNRXNW3D2XSO/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2012:OUSSQ3BWWUZLFXCNRXNW3D2XSO","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":"f96248ab6a0c628ac84108eb8d259146bb18098907c428ac92fc58704d8fa78f","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.GR","submitted_at":"2012-11-15T17:08:58Z","title_canon_sha256":"ed20c909e8ed19518fb5ad59b8ab0b761369b17f7a7e7ca59858ebd1c1ed9773"},"schema_version":"1.0","source":{"id":"1211.3659","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1211.3659","created_at":"2026-05-18T03:40:39Z"},{"alias_kind":"arxiv_version","alias_value":"1211.3659v1","created_at":"2026-05-18T03:40:39Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1211.3659","created_at":"2026-05-18T03:40:39Z"},{"alias_kind":"pith_short_12","alias_value":"OUSSQ3BWWUZL","created_at":"2026-05-18T12:27:16Z"},{"alias_kind":"pith_short_16","alias_value":"OUSSQ3BWWUZLFXCN","created_at":"2026-05-18T12:27:16Z"},{"alias_kind":"pith_short_8","alias_value":"OUSSQ3BW","created_at":"2026-05-18T12:27:16Z"}],"graph_snapshots":[{"event_id":"sha256:34c8d6575aaee3dd43e3b1e72054c5a5e9b2b6fe5397da38645891292a7c048f","target":"graph","created_at":"2026-05-18T03:40:39Z","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":"We consider the problem of finding a color scale which performs well when converted to a grayscale. We assume that each color is converted to a shade of gray with the same intensity as the color. We also assume that the color scales have a linear variation of intensity and hue, and find scales which maximize the average chroma (or \"colorfulness\") of the colors. We find two classes of solutions, which traverse the color wheel in opposite directions. The two classes of scales start with hues near cyan and red. The average chroma of the scales are 65-77% those of the pure colors.","authors_text":"Silas Alben","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.GR","submitted_at":"2012-11-15T17:08:58Z","title":"Color scales that are effective in both color and grayscale"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1211.3659","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":"sha256:7cfe16c713e7458b331392e2df28337d07971adc59893adb06a82f36a6954075","target":"record","created_at":"2026-05-18T03:40:39Z","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":"f96248ab6a0c628ac84108eb8d259146bb18098907c428ac92fc58704d8fa78f","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.GR","submitted_at":"2012-11-15T17:08:58Z","title_canon_sha256":"ed20c909e8ed19518fb5ad59b8ab0b761369b17f7a7e7ca59858ebd1c1ed9773"},"schema_version":"1.0","source":{"id":"1211.3659","kind":"arxiv","version":1}},"canonical_sha256":"7525286c36b532b2dc4d8ddb6d8f57938cdaaee49996b0467f193fdb393cca37","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"7525286c36b532b2dc4d8ddb6d8f57938cdaaee49996b0467f193fdb393cca37","first_computed_at":"2026-05-18T03:40:39.147306Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:40:39.147306Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"4pxid2aiw/GbxTY55O60Ib69aYRSwe6vbEQWYQBQOx7aOO464+QFL14i9fCVIfF1swRhr9S4h6jYq1kyfFcbBQ==","signature_status":"signed_v1","signed_at":"2026-05-18T03:40:39.148147Z","signed_message":"canonical_sha256_bytes"},"source_id":"1211.3659","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:7cfe16c713e7458b331392e2df28337d07971adc59893adb06a82f36a6954075","sha256:34c8d6575aaee3dd43e3b1e72054c5a5e9b2b6fe5397da38645891292a7c048f"],"state_sha256":"3f85e8844d910d1ac72c539a99b01ac399477301d13f5d3b56cb5766c49e361b"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ymw1l2tzUf9FLLzVAzU5+Ce9dDuGjb3JwE8Acp2W9QGLvk9sEVd6dyVPNmCHGYy+JcHeFgdigMLn19DG6hoiAg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-26T02:25:58.043811Z","bundle_sha256":"ee8c46e6132fbb79ad909b1cb9bca3325374bd4220037543bf9bb29bc49805b2"}}