1. A method for verifying an authenticity and integrity of an ordered sequence of digital video frames, the video frames including respective data, the digital video frames including Inter frames and Intra frames both including segments, the segments of the Inter frames including Inter segments and Intra segments, the segments of the Intra frames including Intra segments, the method comprising: a) providing at least one secret key; b) protecting the sequence by embedding a respective calculated digital signature in a least one video frame to produce a protected sequence: i) each said calculated digital signature being dependent on the data of another video frame; ii) each said calculated digital signature being generated using one of said at least one secret key; and iii) each said calculated digital signature being embedded according to an embedded pattern; and compressing the sequence into a bit stream according to a video compression method; wherein: a) said step of embedding is only performed if data dependent embedding criteria are satisfied; b) said step of embedding is only performed into an associated transform coefficient, said associated transform coefficient being pointed to by said embedded pattern; c) said embedding criteria are selected from a group of conditions, such that a visual degradation of the video frames is minimized; and d) said group of conditions includes: i) an absolute value of an associated transform coefficient exceeds a first predetermined value; ii) an associated motion vector exceeds a second predetermined value; and iii) an associated quantization be at most as great as a third predetermined value.