The video verifier application is used to check whether AVI video files that have been created by SurvayaCam, by either local recording or archive exporting, have been modified.

When an AVI video file is created by SurvayaCam encrypted data is also inserted in to the file take contains details about your SurvayaCam system as well as the original format and quality settings that the AVI file was recorded at.

To verify an AVI video file you must have the video verifier installed. Once installed you can right-click on any AVI video file and select the “Verify with SurvayaCam” option from the menu. The option will instruct the video verifier to open the file and check that the original details stored in the file still match the current details of the file.

If all the data is still in the AVI video file and the video format and quality of the video are still the same as at the time of recording then the video verifier will inform you that the file has been verified and will then display the SurvayaCam system information stored in the file. If the details no longer match then the video verifier will inform you that the file has been changed, and where possible is will give you the details of what has been modified.

The video verifier gives you a secure, reliable way of checking that the video you are watching is the original recording of the event. However, if you do not have the video verifier installed you can still perform a less in-depth check to see whether the video file has been modified.

Every frame of video in the AVI video file should have a date and time stamp positioned at the top left-hand side of the video. This stamp should never be missing and the time should be consistently incrementing (Note: AVI video files that have been exported from an archive stream may have inconsistent incrementing due to slow connections and variable frame rates).

There are also two other stamps put on to the video, these are the unique ID for the transmitter that recorded the video that is positioned at the top right-hand side of the video, and the SurvayaCam watermark. The watermark is a small white SurvayaCam logo that is position at the bottom right-hand side of the video.

Both the date/time and unique ID stamps are displayed as black text with a white border around each character. Between characters you should be able to see the video behind, no background to the text should be present.

If any one of these three stamps are missing or are not as describe above then the AVI video file has been modified and its use as evidence will have compromised.

The SurvayaCam system information that is stored in every AVI video file that has been created by SurvayaCam stores information not only about the video format and quality but also the transmitter information, user information and more. Below is a list of the details stored in the AVI video files.

Transmitter Information
The information stored about the transmitter is the system code of the SurvayaCam system, the unique ID of the transmitter, the name of the transmitter, and the MAC address of the PC that the transmitter was running on.

File Information
The information stored about the file is the file type, which will be shown as Local Recording or Exported From Archive. The original file name that the file was created with and the file size are also stored.

Format Information
The information stored about the video format is the dimensions of the video frames, the video codec used to compress the video, an indicator to show whether audio was also recorded and if so the audio codec will be shown. The frame rate of the video is also stored.

File Date/Time Information
The information stored about the date and time is the record start and stop dates and times, the duration of the file, and the duration of the video data.

Linked File Information
This information indicates whether a linked file was also created. A linked file is a recording, either archive or local recording, that was also recording at the same time by the same transmitter. This information allows you to find the archive file that was recorded at the same time as a local recording or visa-versa.

Archive File Information
This information is only shown when the AVI video file has been created from an exported archive file. The information stored about the archive is the is the archive record start and stop dates and times, the duration of the archive file, and the username and full name of the user that exported the archive. An indicator to show whether drawings have been applied to the video is also shown.