An embodiment of an apparatus to authenticate a sequence of video frames includes a process to choose intra-frames of the sequence and sample DC components thereof to produce a set of test fingerprints. To reduce a dimensionality of the test fingerprints, the DC components of the chosen intra-frames are multiplied by a projection matrix formed of eigenvectors associated with the larger eigenvalues of a covariance matrix for a library of frames. The projected test fingerprints are compared against a reference set of fingerprints for authentication. Time-stamp spacings of the chosen intra-frames are determined, and these spacings are employed to select candidate frames for authentication in the reference set of fingerprints.