Mahjong
type: MusicGroup
description: Mahjong is a tile-based game that was developed in the 19th century in China and has spread throughout the world since the early 20th century. It is played by four players (with three-player variation
popularity: 3
followers: 204
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0xecc91869c2d4d3d16199e1d22bd0720fa3ae3d39bf4e8efb8f700e08c1b63405
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 953885
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/953885
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/0adfd204-58a0-4fc2-8e89-70a24797d661.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/0adfd204-58a0-4fc2-8e89-70a24797d661.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/0adfd204-58a0-4fc2-8e89-70a24797d661
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-16T04:12:47Z
additional property: OTSCanonicalRecord
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 0xecc91869c2d4d3d16199e1d22bd0720fa3ae3d39bf4e8efb8f700e08c1b63405. Chain 2 (Bitcoin): anchored in block 953885 (2026-06-16T04:12:47Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/0adfd204-58a0-4fc2-8e89-70a24797d661.json and https://artists.proofprofile.net/proofs/artist/0adfd204-58a0-4fc2-8e89-70a24797d661.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-16T04:12:47Z
album: Blue
  type: MusicAlbum
  date published: 2021-05-21
album: Waves
  type: MusicAlbum
  date published: 2021-06-03
album: Blue
  type: MusicAlbum
  date published: 2021-06-03
album: Linden
  type: MusicAlbum
  date published: 2023-09-08
album: Blackbird
  type: MusicAlbum
  date published: 2023-09-22
album: Blackbird
  type: MusicAlbum
  date published: 2023-10-06
  track: Waited
    type: MusicRecording
    duration: PT2M34S
    duration ms: 154979
    explicit: false
    by artist: Mahjong
    in album: Blackbird
      type: MusicAlbum
      date published: 2023-10-06
    isrc code: TCAHM2344761
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-04T22:38:35+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0xb2c2f014bc6f51a1ec2675a246a0f2db40d5e958fb0e8218c71f9600bda851e5
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 956725
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/956725
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/TCAHM2344761
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-05T01:12:41Z
    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 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 0xb2c2f014bc6f51a1ec2675a246a0f2db40d5e958fb0e8218c71f9600bda851e5. Chain 2 (Bitcoin): anchored in block 956725 (2026-07-05T01:12:41Z), 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/TCAHM2344761.
      date published: 2026-07-05T01:12:41Z
    audio: Waited
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 133.44
      additional property: Musical Key
        type: PropertyValue
        value: 2
      additional property: Mode (Major/Minor)
        type: PropertyValue
        value: 0
      additional property: Time Signature
        type: PropertyValue
        value: 4
      additional property: Danceability
        type: PropertyValue
        value: 0.429
      additional property: Energy
        type: PropertyValue
        value: 0.258
      additional property: Speechiness
        type: PropertyValue
        value: 0.042
      additional property: Acousticness
        type: PropertyValue
        value: 0.757
      additional property: Instrumentalness
        type: PropertyValue
        value: 0.528
      additional property: Liveness
        type: PropertyValue
        value: 0.167
      additional property: Valence (Positivity)
        type: PropertyValue
        value: 0.17
      additional property: Loudness (dB)
        type: PropertyValue
        value: -14.482
      additional property: Key Name
        type: PropertyValue
        value: D
      additional property: Mode Name
        type: PropertyValue
        value: Minor