TimestampCondition

Specifies time limits for matching records, based on the record timestamps.

This parameter accepts a comma-separated list of conditions to match records in the Input0 track with records in the other input track(s).

Each side of a condition must be an expression of the form RecordTime [+/- optional constant], where RecordTime is:

  • startT - the start time of a record from track InputT
  • peakT - the peak time of a record in track InputT
  • endT - the end time of a record in track InputT

In the following example, a record in the Input1 track must start after the record in the Input0 track, but must start not more than two seconds after the end time of the record in the Input0 track.

    TimestampCondition=start1>start0, start1<=end0+2s

Some ESP engines compare a track Input0 with multiple other tracks (InputN, where N>=1). In this case, you can specify different conditions for each InputN track. In the following example, a record in the Input2 track must start after the record in the Input0 track, but must start no more than ten seconds after the end time of the record in the Input0 track:

    TimestampCondition=start1>start0, start1<=end0+2s, start2>start0, start2<=end0+10s

To specify the same conditions for every InputN track (where N>=1), you can use the labels startX, peakX, and endX. This means that the following two examples are equivalent:

    TimestampCondition=start1>start0, start1<=end0+2s, start2>start0, start2<=end0+10s
    TimestampCondition=startX>start0, start1<=end0+2s, start2<=end0+10s

For each track InputN, where N>=1, there must be at least one lower limit for the timestamps (for example startN >= start0 + t), and at least one upper limit (for example startN <= start0 + t). The "Then" (AndThen, AndNotThen, and AndThenAny) ESP engines automatically enforce a lower limit (startX>=start0), so only an upper limit is required. The conditions that you specify are combined together with the AND operator, so a matching record must meet every condition.

NOTE: This parameter is used only when you process video. When you process images or documents, this parameter is ignored and records are considered to be related only if they are associated with the same page.

Type: String
Default:

startX >= start0, startX <= start0

Required: No
Configuration Section: TaskName
Example:
TimestampCondition=startX>start0, start1<=end0+2s, start2<=end0+10s
See Also: