Can the PQA500 be used to detect watermarking or subliminal images?

Can the PQA500 be used to detect watermarking or subliminal images?

The PQA500 does not have any built-in tools to specifically address watermarking or subliminal images however a comparison between PSNR and the human vision model can provide some valuable insights when measuring such video sequences.

For example, if you were to perform a PSNR comparison of an original video clip with no watermark or subliminal images against the same clip after having these items added to it but having no other visual impairments, the resultant difference map would show the absolute impairment introduced by the marking. This would generally show up as a dark gray region in the PSNR difference map.

If you were to then run a PQR or DMOS comparison between these same two video clips, the resultant difference map would show those portions of the watermark or subliminal image that are visible to the average human viewer. This would provide an indication of how subtle the marking is and ideally would be zero or close to zero for completely unobtrusive watermarks.