How to Trim a Video in Adobe Captivate

Video demos are quicker and easier to produce than screen simulations, because instead of generating slides for each interaction, one seamless video is produced. This also means that there’s no filmstrip and only one Timeline, rather than a Timeline for each slide. The Timing Inspector is replaced with Video Effects, which provides some editing tools.

1. After recording the video, click Edit to open the video in Captivate.
   
2. The first 10 seconds will be trimmed by positioning the playhead at the 10 second mark, then clicking Trim.
   
3. Trim Begin and Trim End markers will appear on either side of the playhead.
   
4. Drag each of the Trim markers to the positions on the Timeline that you want to trim. That portion will be shaded in gray. Click the Trim button again. tho delete it.
   
5. If you’ve included mouse actions in the video, but the motions are a little jerky, there is a way to edit the mouse paths. Go to the Edit menu and select Edit Mouse Points.
   
6. Mouse points will appear on the Timeline.
   
7. Click one of the Mouse Points and you’ll see the path of the mouse on the video.
   
8. With the mouse point still selected, go to Video Effects and turn on Smoothen Mouse Path.
    

Source: https://www.webucator.com/article/how-to-trim-a-video-in-adobe-captivate/