Ack van Rooyen
type: MusicGroup
genre: big band
genre: jazz
description: thumb|Van Rooyen in 1995 Ack van Rooyen (1 January 1930, The Hague – 18 November 2021) was a Dutch jazz trumpeter and flugelhornist. He was the brother of Jerry van Rooyen, also a trumpeter-composer.
popularity: 10
followers: 1731
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x73734af7854051c2bca4cb6c4081124ed0ddee36adea8562f205fd126fb98773
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 954784
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/954784
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/e6b1395b-ee2d-4b02-9d0c-7c8ec28726f5.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/e6b1395b-ee2d-4b02-9d0c-7c8ec28726f5.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/e6b1395b-ee2d-4b02-9d0c-7c8ec28726f5
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-22T02:53:59Z
additional property: OTSCanonicalRecord
  type: PropertyValue
  value: {"copyright_id":"0x73734af7854051c2bca4cb6c4081124ed0ddee36adea8562f205fd126fb98773","name":"Ack van Rooyen","registered_at":"2026-06-21T08:44:03Z","symbol":"NIM1878919","token_address":"0x1837eecf67ecdee5a1011f26b1e04dce6a8bbf85","type":"artist","uuid":"e6b1395b-ee2d-4b02-9d0c-7c8ec28726f5"}
additional property: OTSVerifyInstructions
  type: PropertyValue
  value: 1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
  encoding format: application/vnd.opentimestamps.ots
  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x73734af7854051c2bca4cb6c4081124ed0ddee36adea8562f205fd126fb98773. Chain 2 (Bitcoin): anchored in block 954784 (2026-06-22T02:53:59Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/e6b1395b-ee2d-4b02-9d0c-7c8ec28726f5.json and https://artists.proofprofile.net/proofs/artist/e6b1395b-ee2d-4b02-9d0c-7c8ec28726f5.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-22T02:53:59Z
  text: {"copyright_id":"0x73734af7854051c2bca4cb6c4081124ed0ddee36adea8562f205fd126fb98773","name":"Ack van Rooyen","registered_at":"2026-06-21T08:44:03Z","symbol":"NIM1878919","token_address":"0x1837eecf67ecdee5a1011f26b1e04dce6a8bbf85","type":"artist","uuid":"e6b1395b-ee2d-4b02-9d0c-7c8ec28726f5"}
album: Pictures From My Album Of Friends
  type: MusicAlbum
  date published: 1996-06-14
album: Daydream
  type: MusicAlbum
  date published: 1999-08-29
album: Celebration
  type: MusicAlbum
  date published: 2010-01-29
album: Live & In Studio
  type: MusicAlbum
  date published: 2014-06-06
album: Live & In Studio
  type: MusicAlbum
  date published: 2014-06-06
album: Canter No 1
  type: MusicAlbum
  date published: 2021-02-19
album: 90
  type: MusicAlbum
  date published: 2021-04-23