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.

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>.