SSTV Decoder

Demodulate a presented slow-scan-television (SSTV) audio recording, anchor the audio fingerprint and the decoded image hash to the Knox event chain, and return a receipt bundle (Knox anchor + C2PA-aligned envelope + FRE 902(13)/(14)-shape affidavit). Audio bytes are NOT retained — only the SHA-256 fingerprint and the decoded image are anchored. Bonis Systems does not capture audio on its own; the audio must be presented by the caller (a public WebSDR recording, a customer-controlled SDR capture they consent to submit, or audio they own). Phase 1 supports Martin M1 (VIS code 0x2C, 320×256 RGB). Other VIS codes return mode = 'unsupported' with detected hex. Requires a Knox Bearer API key on the Authorization header — unauthenticated calls are rejected.

{
  "type": "object",
  "properties": {
    "name": {
      "type": "string",
      "description": "Display name for the recording (max 256 chars)."
    },
    "audioBase64": {
      "type": "string",
      "description": "Base64-encoded audio. Either a complete WAV file (RIFF/WAVE, 8/16/24-bit PCM or 32-bit IEEE float, mono or stereo, 4-192 kHz) or raw 16-bit signed little-endian mono PCM samples."
    },
    "audioFormat": {
      "type": "string",
      "enum": [
        "wav",
        "pcm16-mono"
      ],
      "description": "Audio container ('wav' default, or 'pcm16-mono')."
    },
    "sampleRate": {
      "type": "integer",
      "minimum": 4000,
      "maximum": 192000,
      "description": "Required when audioFormat = 'pcm16-mono'."
    },
    "capture": {
      "type": "object",
      "description": "Optional capture-context metadata.",
      "properties": {
        "sourceUrl": {
          "type": "string",
          "description": "Audio source URL. Hashed before anchoring; the raw URL is not committed."
        },
        "capturedAt": {
          "type": "string",
          "description": "ISO timestamp when the audio was captured."
        },
        "operatorClaim": {
          "type": "string",
          "description": "Claim about who operated the receiver."
        },
        "callsignClaim": {
          "type": "string",
          "description": "Transmitting callsign claim. Recorded as a claim only — the agent does not verify callsign-to-operator binding."
        }
      }
    }
  },
  "required": [
    "name",
    "audioBase64"
  ],
  "additionalProperties": false
}

Verify a previously anchored SSTV-decode record. Given a SHA-256 anchor hash (the payload_hash from a prior decode_sstv call), return the anchor record, predecessor hash, sequence number, and timestamp. Public — no authentication required. The verification path itself is also accessible at GET /api/knox/verify?hash=<hash>.

{
  "type": "object",
  "properties": {
    "hash": {
      "type": "string",
      "description": "SHA-256 anchor hash (64 lowercase hex chars).",
      "pattern": "^[a-fA-F0-9]{64}$"
    }
  },
  "required": [
    "hash"
  ],
  "additionalProperties": false
}