Is There A Requirement For Security Signatures On Video?

IMHO, most people are concerned about the video at rest on the VMS server (or wherever the video is stored, such as a NAS, SAN, etc.).

The video in transport from camera to VMS can be encrypted, depending on the camera-VMS combination used, but that doesn't usually play in to the watermarking of the recorded video.

On playback of exported video, you should be able to validate the watermark.

Some VMS make a distinction of the validity of the video in the archive vs. archived video that has been exported out of the archive.

Some VMS also will encrypt the data at rest, but I don't think that is as common, and that can't be proven via a watermark.

There are a few layers of signing that are used, not necessarily in order of common to less common:

• Digital watermark/checksum embedded to exported video, which can be verified by a VMS manufacturer provided software tool. Depending on the VMS, encryption and password protection can also be applied during this process.
• Digital watermark embedded in recorded video within the server. This is less common and can increase resource usage on the recorder by 10-20% in my experience.
• Security signature assigned to the file as part of a chain-of-custody investigation software package. This can provide auditing of users that accessed the file, but (I don't believe) could not be used to prove if there was tampering or not. I do not have a background in any systems that do this but have integrated VMSes to a corrections facility management system that claimed to do this.

As UM1 mentioned, a small number of VMSes offer end-to-end encryption (camera to VMS, encrypted at rest in storage, and encrypted on export),  but it is not common, and would not help identify if the video was tampered with. It would simply make it more difficult/unlikely that the video would be accessible to tamper with.