Abstract: Aspects of the subject technology include receiving, by a first device and from a second device, a video of a first subject and indications of one or more select frames from the video, selecting one or more additional frames from the video, generating a first confidence score that the video was captured in a single take based on the one or more select frames and the one or more additional frames, generating a request for proofing an identity of the first subject, and transmitting the request for proofing the identity to a third device. The request for proofing an identity may include the first confidence score.

Abstract: A user device can verify a user's identity to a server while protecting user privacy by not sharing personal data with any other device. To ensure user privacy, the user device performs an enrollment process in which the user performs an action sequence. The user device collects action data from the action sequence and uses the action data locally to generate a set of public/private key pairs (or other representation) from which information about the action sequence cannot be extracted. The public keys, but not the underlying action data, are sent to a server to store. To verify user identity, a user device can repeat the collection of action data and the generation of the key pairs. If the device can prove to the server its possession of the private keys to a sufficient degree, the user's identity can be verified.