Synchronized Viewer

The Synchronized Viewer feature allows you to select a master viewer with which all other viewers will be synchronized. Depending on the applied play mode, the identical time stamp as in the master viewer is displayed in all viewers. The feature is available in the context menu of a viewer (see Context Menu).

IMPORTANT: It is mandatory that all servers including sources and viewer stations are time synchronized (e.g. NTP sync).

We recommend a maximum of 6 viewers in synchronized mode. Any additional viewer could result in a substandard user experience.

Performance

The performance of the synchronized viewer depends mainly on the used parameters:

Database size:

The performance of the synchronized viewer depends on the size of the database, because the time to retrieve synchronized images from the database increases linearly with the size of the database. A long retrieval time of the large database may result in a slow playback speed and low frame rate, resulting in stuttering playback.

Example Test results have confirmed that the lower retrieval performance of large database must be taken into account when using the synchronized viewers, because it has an impact on the viewer playback speed.

Two test scenarios can be distinguished from each other, which clearly show the relationship between database size and playback speed:

1^st scenario: local server, small database (6 TB): short retrieval time and smooth playback.

2^nd scenario: Remote server (connected via LAN), large database (250 TB): long retrieval time and stuttering playback
Viewer count:

Adding more viewers for synchronization may result in lower performance.
Other system parameters:
- FPS of each viewer
- Video formats
- Resolution of the individual viewer recordings

RegistryKeys

There are currently two important RegistryKeys that can be used with the Synchronized Viewer feature. Each RegistryKey has its own results and achieves different behaviors under different conditions.

RegistryKey	Description
FastSyncByBookmark	[HKEY_LOCAL_MACHINE\SOFTWARE\Geutebrueck\Gng\GNGView] "FastSyncByBookmark"=dword:00000001 Current and default behavior. This mode retrieves the images via bookmarks and provides thus a smoother playback and better frame rate (fps). However, in this mode the synchronization is not as accurate (as "FastSyncByTime") and can have time differences in the range of seconds. In this mode, the viewers are not as much dependent on each other. A slow NVR won't affect overall performance much, but it can lead to unsynchronized timestamps within sequences.
FastSyncByTime	[HKEY_LOCAL_MACHINE\SOFTWARE\Geutebrueck\Gng\GNGView] "FastSyncByTime"=dword:00000001 In this mode, the time synchronization is 100% accurate. However, this requires a high power and can thus slow down the playback speed. In this mode, all viewers are interdependent. If there is a slow NVR or slow connection, the overall performance will be affected, resulting in stuttering playback ("slideshow" feeling).

RegistryKey

Description

FastSyncByBookmark

[HKEY_LOCAL_MACHINE\SOFTWARE\Geutebrueck\Gng\GNGView]

"FastSyncByBookmark"=dword:00000001

Current and default behavior. This mode retrieves the images via bookmarks and provides thus a smoother playback and better frame rate (fps). However, in this mode the synchronization is not as accurate (as "FastSyncByTime") and can have time differences in the range of seconds.

In this mode, the viewers are not as much dependent on each other. A slow NVR won't affect overall performance much, but it can lead to unsynchronized timestamps within sequences.

FastSyncByTime

[HKEY_LOCAL_MACHINE\SOFTWARE\Geutebrueck\Gng\GNGView]

"FastSyncByTime"=dword:00000001

In this mode, the time synchronization is 100% accurate. However, this requires a high power and can thus slow down the playback speed.

In this mode, all viewers are interdependent. If there is a slow NVR or slow connection, the overall performance will be affected, resulting in stuttering playback ("slideshow" feeling).