Postcards
type: MusicGroup
popularity: 7
followers: 145
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x3e03113d219a029b5bfa0a043a99858dea40b5083b48627ec3fbe5cdb917b30b
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 954615
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/954615
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/c66a2d33-1033-442e-8213-b02cb8b3086a.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/c66a2d33-1033-442e-8213-b02cb8b3086a.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/c66a2d33-1033-442e-8213-b02cb8b3086a
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-20T22:44:50Z
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 0x3e03113d219a029b5bfa0a043a99858dea40b5083b48627ec3fbe5cdb917b30b. Chain 2 (Bitcoin): anchored in block 954615 (2026-06-20T22:44:50Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/c66a2d33-1033-442e-8213-b02cb8b3086a.json and https://artists.proofprofile.net/proofs/artist/c66a2d33-1033-442e-8213-b02cb8b3086a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-20T22:44:50Z
album: Do I Wanna Know (Acoustic)
  type: MusicAlbum
  date published: 2020-06-29
  track: Do I Wanna Know - Acoustic
    type: MusicRecording
    duration: PT4M44S
    duration ms: 284630
    explicit: false
    by artist: Postcards
    in album: Do I Wanna Know (Acoustic)
      type: MusicAlbum
      date published: 2020-06-29
    isrc code: QZHZ52035299
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-15T23:44:20+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0x9e0d567f7cfa8c91e0bf166c241382c9039ed07223f83347739d15ff30abae30
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 958216
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/958216
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/QZHZ52035299
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-16T00:00:34Z
    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 0x9e0d567f7cfa8c91e0bf166c241382c9039ed07223f83347739d15ff30abae30. Chain 2 (Bitcoin): anchored in block 958216 (2026-07-16T00:00:34Z), 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/QZHZ52035299.
      date published: 2026-07-16T00:00:34Z
    audio: Do I Wanna Know - Acoustic
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 80.438
      additional property: Musical Key
        type: PropertyValue
        value: 7
      additional property: Mode (Major/Minor)
        type: PropertyValue
        value: 0
      additional property: Time Signature
        type: PropertyValue
        value: 4
      additional property: Danceability
        type: PropertyValue
        value: 0.407
      additional property: Energy
        type: PropertyValue
        value: 0.488
      additional property: Speechiness
        type: PropertyValue
        value: 0.027
      additional property: Acousticness
        type: PropertyValue
        value: 0.323
      additional property: Instrumentalness
        type: PropertyValue
        value: 0
      additional property: Liveness
        type: PropertyValue
        value: 0.138
      additional property: Valence (Positivity)
        type: PropertyValue
        value: 0.118
      additional property: Loudness (dB)
        type: PropertyValue
        value: -5.745
      additional property: Key Name
        type: PropertyValue
        value: G
      additional property: Mode Name
        type: PropertyValue
        value: Minor
album: Open Your Eyes (Acoustic)
  type: MusicAlbum
  date published: 2020-07-26
album: Pyro (Acoustic)
  type: MusicAlbum
  date published: 2021-02-16
album: Miss You Love (Cover)
  type: MusicAlbum
  date published: 2021-04-01
album: Green Eyes (Cover)
  type: MusicAlbum
  date published: 2021-08-10
album: 505 - Acoustic (Cover)
  type: MusicAlbum
  date published: 2023-10-17
  track: 505 - Acoustic - Cover
    type: MusicRecording
    duration: PT4M16S
    duration ms: 256519
    explicit: false
    by artist: Postcards
    in album: 505 - Acoustic (Cover)
      type: MusicAlbum
      date published: 2023-10-17
    isrc code: QZTVM2398431
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-20T05:20:38+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0xa331844cf1e96352fdb23b188ea31c5d63c47823d4606dbfdaa84b8099dbd564
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 958832
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/958832
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/QZTVM2398431
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-20T08:21:51Z
    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 0xa331844cf1e96352fdb23b188ea31c5d63c47823d4606dbfdaa84b8099dbd564. Chain 2 (Bitcoin): anchored in block 958832 (2026-07-20T08:21:51Z), 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/QZTVM2398431.
      date published: 2026-07-20T08:21:51Z
    audio: 505 - Acoustic - Cover
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 139.89
      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: 0.431
      additional property: Energy
        type: PropertyValue
        value: 0.513
      additional property: Speechiness
        type: PropertyValue
        value: 0.032
      additional property: Acousticness
        type: PropertyValue
        value: 0.257
      additional property: Instrumentalness
      additional property: Liveness
      additional property: Valence (Positivity)
      additional property: Loudness (dB)
      additional property: Key Name
      additional property: Mode Name
album: Speed of Sound (Acoustic)

Instrumentalness
type: PropertyValue
value: 0

Liveness
type: PropertyValue
value: 0.292

Valence (Positivity)
type: PropertyValue
value: 0.205

Loudness (dB)
type: PropertyValue
value: -7.219

Key Name
type: PropertyValue
value: A

Mode Name
type: PropertyValue
value: Minor

Speed of Sound (Acoustic)
type: MusicAlbum
date published: 2024-10-13