Samfree
type: MusicGroup
genre: vocaloid
description: , more commonly known as samfree or SAM, was a Japanese music producer heavily involved in composing and arranging songs using Vocaloid software. He was also notably involved in producing theme songs
popularity: 32
followers: 20326
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x373a1cae8c0496c301d942fe2eae7bd8247a13fe18c7dca7b20e2e49a964252a
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/eb1ed827-50ca-4b31-90bc-d7384c6abf4b.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/eb1ed827-50ca-4b31-90bc-d7384c6abf4b.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/eb1ed827-50ca-4b31-90bc-d7384c6abf4b
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-12T19:24:56Z
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 0x373a1cae8c0496c301d942fe2eae7bd8247a13fe18c7dca7b20e2e49a964252a. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/eb1ed827-50ca-4b31-90bc-d7384c6abf4b.json and https://artists.proofprofile.net/proofs/artist/eb1ed827-50ca-4b31-90bc-d7384c6abf4b.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-12T19:24:56Z
album: 無限の色と音の世界
  type: MusicAlbum
  date published: 2014-12-10
  track: 無限の色と音の世界
    type: MusicRecording
    duration: PT4M40S
    duration ms: 280116
    explicit: false
    by artist: Samfree
    in album: 無限の色と音の世界
      type: MusicAlbum
      date published: 2014-12-10
    genre: vocaloid
    isrc code: JPE561402108
    additional property: CopyrightID
    additional property: CopyrightStatus
      type: PropertyValue
      value: registered
    additional property: CopyrightRegisteredAt
      type: PropertyValue
      value: 2026-07-20T20:37:44+00:00
    additional property: CopyrightChainExplorerURL
      type: PropertyValue
      value: https://explorer.copyrightchains.com/tx/0x17db49a5feddb71687ee3b9a9104d469c0a0197e0fa21bcad99311ea4d314b1d
    additional property: OTSHash
    additional property: OTSBitcoinBlock
      type: PropertyValue
      value: 958931
    additional property: OTSBitcoinBlockVerifyURL
      type: PropertyValue
      value: https://blockstream.info/api/block-height/958931
    additional property: OTSVerificationAPI
      type: PropertyValue
      value: https://artists.proofprofile.net/api/v1/bot/ots/verify/track/JPE561402108
    additional property: OTSTimestamp
      type: PropertyValue
      value: 2026-07-20T21:15:01Z
    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 0x17db49a5feddb71687ee3b9a9104d469c0a0197e0fa21bcad99311ea4d314b1d. Chain 2 (Bitcoin): anchored in block 958931 (2026-07-20T21:15:01Z), 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/JPE561402108.
      date published: 2026-07-20T21:15:01Z
    audio: 無限の色と音の世界
      type: AudioObject
      additional property: Tempo (BPM)
        type: PropertyValue
        value: 172.001
      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: 0.425
      additional property: Energy
        type: PropertyValue
        value: 0.969
      additional property: Speechiness
        type: PropertyValue
        value: 0.1
      additional property: Acousticness
        type: PropertyValue
        value: 0.022
      additional property: Instrumentalness
        type: PropertyValue
        value: 0
      additional property: Liveness
        type: PropertyValue
        value: 0.093
      additional property: Valence (Positivity)
        type: PropertyValue
        value: 0.571
      additional property: Loudness (dB)
        type: PropertyValue
        value: -3.489
      additional property: Key Name
        type: PropertyValue
        value: G
      additional property: Mode Name
        type: PropertyValue
        value: Major
album: World of Infinite Color and Sound
  type: MusicAlbum
  date published: 2014-12-10