瀬川瑛子
type: MusicGroup
genre: enka
genre: kayokyoku
popularity: 23
followers: 2025
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0xbc640a4a3921fb334e6afc03f4cba4c29e815654b468c3dcdcc59a682d6999fc
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 953407
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/953407
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/3fe3f30b-07be-4b07-8b69-0a690023702a.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/3fe3f30b-07be-4b07-8b69-0a690023702a.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/3fe3f30b-07be-4b07-8b69-0a690023702a
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-12T19:24:56Z
additional property: OTSCanonicalRecord
  type: PropertyValue
  value: {"copyright_id":"0xbc640a4a3921fb334e6afc03f4cba4c29e815654b468c3dcdcc59a682d6999fc","name":"瀬川瑛子","registered_at":"2026-06-11T17:33:27Z","symbol":"NIM0083574","token_address":"0xea1714ba9f1da1da2180cbb930a0fb7cedfe70f3","type":"artist","uuid":"3fe3f30b-07be-4b07-8b69-0a690023702a"}
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 0xbc640a4a3921fb334e6afc03f4cba4c29e815654b468c3dcdcc59a682d6999fc. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/3fe3f30b-07be-4b07-8b69-0a690023702a.json and https://artists.proofprofile.net/proofs/artist/3fe3f30b-07be-4b07-8b69-0a690023702a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-12T19:28:13Z
  text: {"copyright_id":"0xbc640a4a3921fb334e6afc03f4cba4c29e815654b468c3dcdcc59a682d6999fc","name":"瀬川瑛子","registered_at":"2026-06-11T17:33:27Z","symbol":"NIM0083574","token_address":"0xea1714ba9f1da1da2180cbb930a0fb7cedfe70f3","type":"artist","uuid":"3fe3f30b-07be-4b07-8b69-0a690023702a"}
album: 二人羽織／父娘酒
  type: MusicAlbum
  date published: 2020-05-13
album: 瀬川瑛子全曲集 ～二人羽織・命くれない～
  type: MusicAlbum
  date published: 2020-09-02
  track: わすれ宿
    type: MusicRecording
    duration: PT3M59S
    duration ms: 239613
    explicit: false
    by artist: 瀬川瑛子
    in album: 瀬川瑛子全曲集 ～二人羽織・命くれない～
      type: MusicAlbum
      date published: 2020-09-02
    genre: enka
    genre: kayokyoku
    isrc code: JPCR00503580
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-04T21:29:55+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0xcbad0bec4d47590e777fab298cb646db0cc1fc59d438d9924d945fcbbef86ca3
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 956728
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/956728
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPCR00503580
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-05T01:43:49Z
    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 0xcbad0bec4d47590e777fab298cb646db0cc1fc59d438d9924d945fcbbef86ca3. Chain 2 (Bitcoin): anchored in block 956728 (2026-07-05T01:43:49Z), 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/JPCR00503580.
      date published: 2026-07-05T01:43:49Z
    audio: わすれ宿
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 127.9
      additional property: Musical Key
        type: PropertyValue
        value: 5
      additional property: Mode (Major/Minor)
        type: PropertyValue
        value: 0
      additional property: Time Signature
        type: PropertyValue
        value: 4
      additional property: Danceability
        type: PropertyValue
        value: 0.515
      additional property: Energy
        type: PropertyValue
        value: 0.456
      additional property: Speechiness
        type: PropertyValue
        value: 0.027
      additional property: Acousticness
        type: PropertyValue
        value: 0.657
      additional property: Instrumentalness
        type: PropertyValue
        value: 0.003
      additional property: Liveness
        type: PropertyValue
        value: 0.168
      additional property: Valence (Positivity)
        type: PropertyValue
        value: 0.367
      additional property: Loudness (dB)
        type: PropertyValue
        value: -6.123
      additional property: Key Name
        type: PropertyValue
        value: F
      additional property: Mode Name
        type: PropertyValue
        value: Minor
  track: 笑いじわ
    type: MusicRecording
    duration: PT3M41S
    duration ms: 221773
    explicit: false
    by artist: 瀬川瑛子
    in album: 瀬川瑛子全曲集 ～二人羽織・命くれない～
      type: MusicAlbum
      date published: 2020-09-02
    genre: enka
    genre: kayokyoku
    isrc code: JPCR09508330
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-04T03:58:47+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0x5b61040292fe190b74f18169f5332e6816780dd668ef2da4d8ed41fb4f8ac347
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 956639
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/956639
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPCR09508330
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-04T11:19:20Z
    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 0x5b61040292fe190b74f18169f5332e6816780dd668ef2da4d8ed41fb4f8ac347. Chain 2 (Bitcoin): anchored in block 956639 (2026-07-04T11:19:20Z), 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/JPCR09508330.
      date published: 2026-07-04T11:19:20Z
    audio: 笑いじわ
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 142.903
      additional property: Musical Key
        type: PropertyValue
        value: 0
      additional property: Mode (Major/Minor)
        type: PropertyValue
        value: 0
      additional property: Time Signature
        type: PropertyValue
        value: 4
      additional property: Danceability
        type: PropertyValue
        value: 0.674
      additional property: Energy
        type: PropertyValue
        value: 0.689
      additional property: Speechiness
        type: PropertyValue
        value: 0.029
      additional property: Acousticness
        type: PropertyValue
        value: 0.647
      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: いのちの人よ／夢の中で
album: 瀬川瑛子全曲集〜いのちの人よ・命くれない〜
album: 愛恋川
album: 愛恋川／黄昏みなと
album: めおと浜唄／ブルースを聞かせて
album: 萩の宿～令和ヴァージョン～／春の海～令和ヴァージョン～

Liveness
type: PropertyValue
value: 0.077

Valence (Positivity)
type: PropertyValue
value: 0.822

Loudness (dB)
type: PropertyValue
value: -4.851

Key Name
type: PropertyValue
value: C

Mode Name
type: PropertyValue
value: Minor

いのちの人よ／夢の中で
type: MusicAlbum
date published: 2021-03-31

瀬川瑛子全曲集〜いのちの人よ・命くれない〜
type: MusicAlbum
date published: 2021-10-06

愛恋川
type: MusicAlbum
date published: 2022-09-07

愛恋川／黄昏みなと
type: MusicAlbum
date published: 2022-09-28

めおと浜唄／ブルースを聞かせて
type: MusicAlbum
date published: 2024-05-22
track: めおと浜唄
  type: MusicRecording
  duration: PT4M1S
  duration ms: 241146
  explicit: false
  by artist: 瀬川瑛子
  in album: めおと浜唄／ブルースを聞かせて
    type: MusicAlbum
    date published: 2024-05-22
  genre: enka
  genre: kayokyoku
  isrc code: JPCR02401390
  additional property: CopyrightID
  additional property: CopyrightStatus
    type: PropertyValue
    value: registered
  additional property: CopyrightRegisteredAt
    type: PropertyValue
    value: 2026-07-16T15:22:48+00:00
  additional property: CopyrightChainExplorerURL
    type: PropertyValue
    value: https://explorer.copyrightchains.com/tx/0x25f02fde4d1b13f2b2301c5217b49d0b8c8badff626623a81e25b89baaabe9ea
  additional property: OTSHash
  additional property: OTSBitcoinBlock
    type: PropertyValue
    value: 958300
  additional property: OTSBitcoinBlockVerifyURL
    type: PropertyValue
    value: https://blockstream.info/api/block-height/958300
  additional property: OTSVerificationAPI
    type: PropertyValue
    value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPCR02401390
  additional property: OTSTimestamp
    type: PropertyValue
    value: 2026-07-16T16:14:30Z
  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 0x25f02fde4d1b13f2b2301c5217b49d0b8c8badff626623a81e25b89baaabe9ea. Chain 2 (Bitcoin): anchored in block 958300 (2026-07-16T16:14:30Z), 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/JPCR02401390.
    date published: 2026-07-16T16:14:30Z
  audio: めおと浜唄
    type: AudioObject
    additional property: Tempo (BPM)
      type: PropertyValue
      value: 143.769
    additional property: Musical Key
      type: PropertyValue
      value: 0
    additional property: Mode (Major/Minor)
      type: PropertyValue
      value: 1
    additional property: Time Signature
      type: PropertyValue
      value: 4
    additional property: Danceability
      type: PropertyValue
      value: 0.474
    additional property: Energy
      type: PropertyValue
      value: 0.754
    additional property: Speechiness
      type: PropertyValue
      value: 0.043
    additional property: Acousticness
      type: PropertyValue
      value: 0.152
    additional property: Instrumentalness
      type: PropertyValue
      value: 0
    additional property: Liveness
      type: PropertyValue
      value: 0.19
    additional property: Valence (Positivity)
      type: PropertyValue
      value: 0.71
    additional property: Loudness (dB)
      type: PropertyValue
      value: -3.536
    additional property: Key Name
      type: PropertyValue
      value: C
    additional property: Mode Name
      type: PropertyValue
      value: Major

萩の宿～令和ヴァージョン～／春の海～令和ヴァージョン～
type: MusicAlbum
date published: 2025-08-20