伊藤つかさ
type: MusicGroup
genre: city pop
genre: j-pop
genre: kayokyoku
popularity: 7
followers: 3025
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0xfa7c423094cb0d6eb8744b3eb06aedd2f9d086521dd54e43e57841b2cf811120
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 954659
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/954659
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/dcf4e924-811d-4d7c-a88b-2fb39d84e3bb.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/dcf4e924-811d-4d7c-a88b-2fb39d84e3bb.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/dcf4e924-811d-4d7c-a88b-2fb39d84e3bb
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-21T06:14:42Z
additional property: OTSCanonicalRecord
  type: PropertyValue
  value: {"copyright_id":"0xfa7c423094cb0d6eb8744b3eb06aedd2f9d086521dd54e43e57841b2cf811120","name":"伊藤つかさ","registered_at":"2026-06-21T05:16:32Z","symbol":"NIM1831231","token_address":"0xdaf776db8fa72a12e207c58e78934226f9c4b7e0","type":"artist","uuid":"dcf4e924-811d-4d7c-a88b-2fb39d84e3bb"}
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
subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
  encoding format: application/vnd.opentimestamps.ots
  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfa7c423094cb0d6eb8744b3eb06aedd2f9d086521dd54e43e57841b2cf811120. Chain 2 (Bitcoin): anchored in block 954659 (2026-06-21T06:14:42Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/dcf4e924-811d-4d7c-a88b-2fb39d84e3bb.json and https://artists.proofprofile.net/proofs/artist/dcf4e924-811d-4d7c-a88b-2fb39d84e3bb.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-21T06:14:42Z
  text: {"copyright_id":"0xfa7c423094cb0d6eb8744b3eb06aedd2f9d086521dd54e43e57841b2cf811120","name":"伊藤つかさ","registered_at":"2026-06-21T05:16:32Z","symbol":"NIM1831231","token_address":"0xdaf776db8fa72a12e207c58e78934226f9c4b7e0","type":"artist","uuid":"dcf4e924-811d-4d7c-a88b-2fb39d84e3bb"}
album: クレッシェンド
  type: MusicAlbum
  date published: 1984-05-21
  track: 若葉のころ
    type: MusicRecording
    duration: PT4M41S
    duration ms: 281838
    explicit: false
    by artist: 伊藤つかさ
    in album: クレッシェンド
      type: MusicAlbum
      date published: 1984-05-21
    genre: city pop
    genre: j-pop
    genre: kayokyoku
    isrc code: JPVI08408600
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-21T19:50:21+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0x01eaf34398e4ed0decb95b727b5d71a2e7107adbb624055ad27a7df11a8e5bd7
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 959054
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/959054
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPVI08408600
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-21T22:51:52Z
    additional property: OTSVerifyInstructions
      type: PropertyValue
      value: 1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp
    subject of: OpenTimestamps Proof of Existence
      type: DigitalDocument
      encoding format: application/vnd.opentimestamps.ots
      description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x01eaf34398e4ed0decb95b727b5d71a2e7107adbb624055ad27a7df11a8e5bd7. Chain 2 (Bitcoin): anchored in block 959054 (2026-07-21T22:51:52Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPVI08408600.
      date published: 2026-07-21T22:51:52Z
    audio: 若葉のころ
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 116.449
      additional property: Musical Key
        type: PropertyValue
        value: 7
      additional property: Mode (Major/Minor)
        type: PropertyValue
        value: 1
      additional property: Time Signature
        type: PropertyValue
        value: 4
      additional property: Danceability
        type: PropertyValue
        value: 0.764
      additional property: Energy
        type: PropertyValue
        value: 0.375
      additional property: Speechiness
        type: PropertyValue
        value: 0.035
      additional property: Acousticness
        type: PropertyValue
        value: 0.439
      additional property: Instrumentalness
        type: PropertyValue
        value: 0
      additional property: Liveness
        type: PropertyValue
        value: 0.107
      additional property: Valence (Positivity)
        type: PropertyValue
        value: 0.426
      additional property: Loudness (dB)
        type: PropertyValue
        value: -16.049
      additional property: Key Name
        type: PropertyValue
        value: G
      additional property: Mode Name
        type: PropertyValue
        value: Major
  track: 涙のクレッシェンド
    type: MusicRecording
    duration: PT4M32S
    duration ms: 272695
    explicit: false
    by artist: 伊藤つかさ
    in album: クレッシェンド
      type: MusicAlbum
      date published: 1984-05-21
    genre: city pop
    genre: j-pop
    genre: kayokyoku
    isrc code: JPVI08311800
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-21T13:01:47+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0xc54a69282796ae72dd230e65f2e0a3d9c289cb11b6988937e8db76643c487922
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 959008
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/959008
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPVI08311800
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-21T16:02:31Z
    additional property: OTSVerifyInstructions
      type: PropertyValue
      value: 1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp
    subject of: OpenTimestamps Proof of Existence
      type: DigitalDocument
      encoding format: application/vnd.opentimestamps.ots
      description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc54a69282796ae72dd230e65f2e0a3d9c289cb11b6988937e8db76643c487922. Chain 2 (Bitcoin): anchored in block 959008 (2026-07-21T16:02:31Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPVI08311800.
      date published: 2026-07-21T16:02:31Z
    audio: 涙のクレッシェンド
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 103.368
      additional property: Musical Key
        type: PropertyValue
        value: 6
      additional property: Mode (Major/Minor)
        type: PropertyValue
        value: 0
      additional property: Time Signature
        type: PropertyValue
        value: 4
      additional property: Danceability
        type: PropertyValue
        value: 0.668
      additional property: Energy
        type: PropertyValue
        value: 0.314
      additional property: Speechiness
        type: PropertyValue
        value: 0.033
      additional property: Acousticness
        type: PropertyValue
        value: 0.756
      additional property: Instrumentalness
        type: PropertyValue
        value: 0
      additional property: Liveness
      additional property: Valence (Positivity)
      additional property: Loudness (dB)
      additional property: Key Name
      additional property: Mode Name
album: オススメ！

Liveness
type: PropertyValue
value: 0.108

Valence (Positivity)
type: PropertyValue
value: 0.362

Loudness (dB)
type: PropertyValue
value: -15.162

Key Name
type: PropertyValue
value: F#

Mode Name
type: PropertyValue
value: Minor

オススメ！
type: MusicAlbum
date published: 1984-12-16