A digital media authentication system comprises a media processing application executed by a mobile electronic device that computes a robust image hash for media data acquired by the mobile electronic device; a location attestation system that validates a location context of the media data, the location context determined in response to an object scene in a field of view of the mobile electronic device captured for conversion to the media data; and a blockchain network that maintains a ledger entry that includes the robust image hash, an immutable timestamp, and a location certificate validating the location context of the media data.