Kontra
type: MusicGroup
description: A kontra (, 'three-stringed viola') is a Hungarian, Czech, Polish, Romanian, Slovak and Romani instrument common in Transylvania. Construction The kontra can be constructed new, but is most often a c
popularity: 15
followers: 64
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x96f2d21018293ca971de01e6db848d03f024b1551fac51eca8cc876d27f5a5b3
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 953842
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/953842
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/eed5c102-48e4-47d3-8d94-069eeb9bf4cd.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/eed5c102-48e4-47d3-8d94-069eeb9bf4cd.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/eed5c102-48e4-47d3-8d94-069eeb9bf4cd
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-15T22:22:30Z
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
subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
  encoding format: application/vnd.opentimestamps.ots
  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x96f2d21018293ca971de01e6db848d03f024b1551fac51eca8cc876d27f5a5b3. Chain 2 (Bitcoin): anchored in block 953842 (2026-06-15T22:22:30Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/eed5c102-48e4-47d3-8d94-069eeb9bf4cd.json and https://artists.proofprofile.net/proofs/artist/eed5c102-48e4-47d3-8d94-069eeb9bf4cd.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-15T22:22:30Z
album: Aperol
  type: MusicAlbum
  date published: 2025-02-14
album: Luna rossa
  type: MusicAlbum
  date published: 2025-03-28
album: Aroma
  type: MusicAlbum
  date published: 2025-05-19
album: Santorini
  type: MusicAlbum
  date published: 2025-06-14
  track: Santorini
    type: MusicRecording
    duration: PT2M41S
    duration ms: 161684
    explicit: false
    by artist: Kontra
    in album: Santorini
      type: MusicAlbum
      date published: 2025-06-14
    isrc code: QZTB32554190
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-13T00:53:03+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0x34b983029458370d088a81a52649783f7c0bf487b80318e3ed8560299df1bd37
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 957785
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/957785
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/QZTB32554190
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-13T01:55:31Z
    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 0x34b983029458370d088a81a52649783f7c0bf487b80318e3ed8560299df1bd37. Chain 2 (Bitcoin): anchored in block 957785 (2026-07-13T01:55:31Z), 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/QZTB32554190.
      date published: 2026-07-13T01:55:31Z
    audio: Santorini
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 94.912
      additional property: Musical Key
        type: PropertyValue
        value: 9
      additional property: Mode (Major/Minor)
        type: PropertyValue
        value: 0
      additional property: Time Signature
        type: PropertyValue
        value: 4
      additional property: Danceability
        type: PropertyValue
        value: 0.703
      additional property: Energy
        type: PropertyValue
        value: 0.674
      additional property: Speechiness
        type: PropertyValue
        value: 0.037
      additional property: Acousticness
        type: PropertyValue
        value: 0.768
      additional property: Instrumentalness
        type: PropertyValue
        value: 0
      additional property: Liveness
        type: PropertyValue
        value: 0.121
      additional property: Valence (Positivity)
        type: PropertyValue
        value: 0.418
      additional property: Loudness (dB)
        type: PropertyValue
        value: -6.601
      additional property: Key Name
        type: PropertyValue
        value: A
      additional property: Mode Name
        type: PropertyValue
        value: Minor
album: Epikindini
  type: MusicAlbum
  date published: 2025-07-18
album: Ithaki Rsr
  type: MusicAlbum
  date published: 2025-08-13
album: Ksana
  type: MusicAlbum
  date published: 2025-09-15