Approach Tech NVR-2018 manual 12-02-02 01-30-03 Lists 2999 02-03-03 3000 02-08-03

10. Index Table

The following description details how the NVR manages an index table issue.

The NVR will generate a time index table indicating recorded data is kept in a particular HDD. This allows to individually selecting recorded data to be displayed via the alarm list search and full list search. The maximum number of lists, for a given HDD, is 3000. When the list of any given HDD is used up-and the disk is not full, The unit will still use the rest of the space for recording. In such a case, an index for the recent recorded data will be generated and the index of the next oldest data will be erased so that the list does remain 3000 in total. And the next oldest data will be kept in the index of the corresponding oldest data. For any newly-recorded data, this approach will be applied until the disk becomes full.

HD1		HD1
1	12-02-02 12:20:55	1	12-02-02 12:20:55
2	12-02-02 13:30:33	2	01-30-03 16:00:34
3	01-30-03 16:00:34		:
3000 LISTS	:		:	3000 LISTS
	:		:
	:	2999	02-03-03 16:00:56
3000	02-03-03 16:00:56	3000	02-08-03 17:30:58

In the rewrite recording mode, when the archived hard disk drive is full, the NVR will start overwriting the oldest data recorded. As the previous recorded data was partially overwritten by the recent recording, the indicating time index of that data will be changed corresponding to the starting time of the remaining session. The index of the session will be deleted from the table when it is fully overwritten.

Previously recorded data overwritten

The point stops recording

Previously recorded data remaining

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