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18.5.4. Tampering/Alteration Check
The viewer software includes a function to check for data tampering or alteration. If altered data is found, an error message is displayed. The Tamper Check key is only available when playback is paused.
1.While playback is paused, press the Tamper Check key. This activates the Tamper/Alteration Check function.
2.Press the Play or Reverse Play button.
For USB memory devices:
Checks the video file frame by frame to discern whether there has been tampering or alteration. Nothing is displayed if no abnormalities are found. If abnormalities are found, then an error message appears and the altered video is paused.
For DVD media:
Confirms whether the DVD is in fact the one copied from the digital video recorder. Nothing is displayed if no abnormalities are found. If the DVD is found to be one other than that copied from the main unit, then an error message appears and the video is paused.
Note
Deactivate "Drive Letter Access (DLA)" when packet writing software is installed in a PC. Otherwise tampering/alteration check does not function correctly. Uncheck the box "Activate drive's DLA" tab in the property of DVD drive.
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