CreateClip

The CreateClip action creates an MP4 clip from a VMS storage area.

When you create a clip from a VMS storage area, the timestamps in the extracted clip are relative to the original wall-clock time. For example, if you request a clip for 14:00 to 15:00, the start of the clip becomes 00:00 and the end of the clip becomes 01:00. Clip timestamps between these values are relative to the original timestamps. For example, to play content from 14:25, seek 25 minutes into the extracted clip so that the time displayed in the media player is 00:25.

If you request a clip but there is a gap in the recording, or at either end of the recording, the output video includes padding frames so that the clip timestamps remain relative to the wall-clock time. Padding frames are black with the text "Content Interrupted".

NOTE:

Sometimes your media player might not show "Content Interrupted" frames, because they are supported only for certain codecs and by certain players. In these cases the media player continues to show the previous frame for the duration of the gap.

If you request a clip but there is no content at all between the start and end times, the output video contains a black frame with the text "No Content".

To check the actual time range used to generate a clip, look in the application log. In the following example there are two time ranges, indicating that there was a gap in the recording:

Finished recording to C:\VMS\saved\temp.mp4, time range(s): 1488285315-1488285398, 1488285427-1488285540

If there is no content at all, VMS logs a message similar to:

No content found between start time 1519007000 and end time 1519008000

Parameter Description Required
AuthToken The authentication token to pass to VMS when VMS is configured for token authentication. No
EndFrame The frame number to end on (within the specified EndUTC). The default value is 1. No
EndUTC End time of the clip in epoch seconds. Yes
OutPath The full UNC path to the output file, in MP4 format. If you do not specify a path, the file is saved in the folder specified by FileOutputPath and you can retrieve it using the DownloadClip action. No
StartFrame The frame number to start on (within the specified StartUTC). The default value is 1. No
StartUTC Start time of the clip in epoch seconds. Yes
Track The storage area from which to create the clip (as a number from 0 to 15). Yes

Example

The following example creates a clip from the fourth storage area, with a start time of 1299000000 seconds UTC, an end time of 1299000245 seconds UTC, a start frame of 12, and an end frame of 13.

/action=CreateClip
           &Track=3
           &StartUTC=1299000000
           &StartFrame=12
           &EndUTC=1299000245
           &EndFrame=13
           &OutPath=\\box1\SharedFolder\example_clip3.mp4

_FT_HTML5_bannerTitle.htm