• You can trim undesired content from the beginning or finish of a video or audio clip that you've added to a PowerPoint slide, or both. Only videos that you've inserted from your computer can be trimmed. For videos inserted via the web, this capability is not available.
• Cut a video Select the video border on the slide in Normal view.
• When the video is selected, a Video Tools section with two tabs displays on the toolbar ribbon: Playback and format: Trim Video may be found on the Playback tab of the ribbon, under Video Tools.
• In the Edit Video dialogue box, press the Play button to see where you want to trim your video recording.
• Press the Pause button when you've reached the spot where you wish to make the cut.
• To fine-tune the location of a marking, utilise the Next Frame and Previous Frame buttons.
• Do one or more of the following in the Trim Video dialogue box:
• Click the start point to trim the beginning of the footage ( as a green marker, on the left). Drag the two-headed arrow to a new beginning location for the video when you see it.
• Click the end point to trim the end of the clip (as a red marker, on the right). Drag the two-headed arrow to a new video ending position when you see it.

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